Clay Shirky is a noted internet guru and has written extensively about the nature of the participatory internet. Here are some lessons from his recent book Here come severybody, which is about the importance of contributing to the development the collective internet knowledge base.

The value of Group Action
The loosely affiliated group can accomplish something more effectively than the institution can.
Most of the barriers to group action have collapsed, and without those barriers, we are free to explore new ways of gathering together and getting things done.
The costs incurred by creating a new group or joining an existing one have collapsed, not just in money but in time, effort and attention.
People respond to incentives. If you give them more of a reason to do something, they will do more of it, and if you make it easier to do more of something they are already inclined to do, they will also do more of it.
If you want to organize the work of even dozens of people, you have to manage them. As organizations grow into the hundreds or thousands, you also have to manage the managers. Simply to exist at that size, an organization has to take on the costs of all that management.
None of the absolute advantages of institutions like businesses or schools or governments have disappeared.
The music industry is still reeling from the discovery that the reproduction and distribution of music, previously a valuable service, is now something their customers can do for themselves.
Group action gives society its particular characters, and anything that changes the way groups get things done will affect society as a whole.
For any given organization, the important questions are "When will the change happen?" and "What will change?" The only two answers we can rule out are never and nothing.
Individuals in group settings exhibit behaviors that no one could predict by studying single minds. No one has ever been bashful or extroverted while sitting alone in their room, no one can be a social climber or a man of the people without reference to society, and these characteristics exist because groups are not just simple aggregations of individuals.
Typical organization is hierarchical, which vastly simplifies communication among employees. New employees only need one connection, to their boss, to get started. That's much simpler than trying to have everyone talk to everyone.
Self-preservation of the institution becomes job number one, while its stated goal is relegated to number two or lower, no matter what the mission statement says.
For a group to take collective action, it must have some shared vision strong enough to bind the group together, despite periodic decisions that will inevitably displease at least some members. For this reason collective action is harder to arrange than information sharing or collaborative creation. In the current spread of social tools, real examples of collective action - where a group acts on behalf of, and with shared consequences for, all of its members - are still relatively rare.

Thing of group undertaking as a kind of ladder of activities that are enabled or improved by social tools.
The rungs on the ladder, in order of difficulty, are:
- sharing
- cooperation
- collective action.

Why people join groups
The promise is the basic "why" for anyone to join or contribute to a group.
The tool helps with the "how", for the difficulties of coordination.
The bargain sets the rules of the road: if you are interested in the promise and adopt the tools, what can you expect and what will be expected of you?
Any new claim on someone's time must obviously offer some value, but more important, it must offer some value higher than something else she already does, or she won't free up the time.
The promise has to hit a sweet spot among several extremes. Voice of the Faithful was neither too mundane ("let's blow off steam about abusive priests") nor too disprespectful ("let's demolish the church"). Linux was neither too provisional ("let's try to see if we can come up with something together") nor too sweeping ("let's create a world-changing operating system"). Modest but interesting.
The problem of getting the promise right is unlike traditional marketing, because most marketing involves selling something that will be made for the listeners rather than by them. ("Buy Cheesy Poofs" is a different message from "Join us and let's invent Cheesy Poofs together").
You need to convince individuals not just that they will find the group satisfying and effective but that others will find it so as well.
Founder of Flickr said, "You have to greet the first 10,000 users personally." This let the early users feel what it would be like to have an appreciative public, even before such a public existed.
Bargain helps clarify what you can expect of others and what they can expect of you.
Wikipedia arms its users with ways to help enforce the bargains that make the site work.
Communal bike programs that have succeeded have placed restrictions on the use of the bicycles with things like locked sheds and ID cards for checking them in and out. (Given the opportunity to misbehave and little penalty for doing so, enough people's behavior becomes antisocial enough to wreck things for everyone.)
No effort at creating group value can be successful without some form of governance.
People are basically good, when they are in circumstances that reward goodness while restraining impulses to defect.

Sharing, Cooperating and Collective Action
Sharing creates the fewest demands on the participants. Many sharing platforms like Flikr operate in a take-it-or-leave-it fashion, allowing for the maximum freedom of the individual to participate while creating the fewest complications of group life.
The cost of finding like-minded people has been lowered, and more important : deprofessionalized.
Cooperating is harder than simply sharing, because it involves changing your behavior to sync with people who are changing their behavior to sync with you. Unlike sharing, where the group is mainly an aggregate of participants, cooperating creates group identity - you know who you are cooperating with. One simple form of cooperation is conversation. When people are in one another's company, they like to talk.
Collaborative production is a more involved form of cooperation, as it increases the tension between individual and group goals. The litmus test for is simple : no one person can take credit for what gets created, and the project could not come into being without the participation of many.
Collective action is the hardest kind of group effort, requiring a group of people to commit themselves to undertaking a particular effort together, and to do so in a way that makes the decision of the group binding on the individual members.

Tragedy of the commons:
Where individuals have an incentive to damage the collective good. While each person can agree that all would benefit from common restraint, the incentives of the individuals are arrayed against that outcome. This is why taxes are never voluntary - people would opt out of paying for road maintenance.
Why would anyone (myspace comments, self-absorbed bloggers) put such drivel out in public? It's simple. They're not talking to you. We misread these seemingly inane posts because we're so unused to seeing written material in public that isn't intended for us.
We think that everyone is now broadcasting. This is a mistake. If we listened in on other people's phone calls, we'd know to expect small talk, inside jokes, and the like, but people's phone calls aren't out in the open.
Fame is simply an inbalance between inbound and outbound attention, more arrows pointing in than out.

Two things have to happen for someone to be famous:
1. Scale: an audience in the thousands or more
2. To be unable to reciprocate

Famous means being the recipient of more attention than you can return in any medium.
In the blog world there are no authorities, only masses, and yet the accumulated weight of attention continues to create the kind of imbalances we associate with traditional media.

The downside of fame: being unable to reciprocate in the way our friends and colleagues would like us to.

Publishing and Conversations
Every instance of the written word comes with an implicit promise : someone besides the writer thought this was worth reading.
"Published": The label is a way of assuring people that some external filter has been applied to the work. The converse of this effect explains our skepticism about self-published books and the label reserved for publishers who print such books - the vanity press.
Publishing makes mass amateurization of filtering a forced move.
Filter-then-publish rested on a scarcity of media that is a thing of the past.
The only working system is publish-then-filter.
Conversation is king. Content is just something to talk about. The conversation that forms around shared photos, videos, blog posts, and the like is often about how to do it better next time - how to be a better photographer or a better writer or a better programmer. The goal of getting better at something is different from the goal of being good at it. There is a pleasure in improving your abilities even if that doesn't translate into absolute perfection.
By providing an opportunity for the visible display of expertise or talent, the public asking of questions creates a motivation to answer in public as well, and that answer, once perfected, persists even if both the original asker and answerer lose interest.
With a billion people online, it's easy and cheap to get the attention of a million people, or more important, help those people get one another's attention.
People like to consume media, but they also like to produce it ("Look what I made!") and share it ("Look what I found!").
Communications tools don't get socially interesting until they get technologically boring.
The hallmark of revolution is that the goals of the revolutionaries cannot be contained by the institutional structure of the existing society.

How Wikipedia Works:
Something this big seems like it should require managers, a formal work-flow process. How (else) could it possibly work? Spontaneous division of labor.
Someone decides an article should exist and creates it. That article's creator doesn't need to know everything. Some add new text, some edit. None of these people need to know everything.
For a Wikipedia article to improve, the good edits simply have to outweigh the bad ones.
There is simply no commercially viable way to let employees work on what interest them as the mood strikes. There is, however, a noncommercial way to do so, which involves being effective without worrying about being efficient.
This is what befell Nupedia: because everyone working on that project understood that only experts were to write articles, no one would even begin an article they knew little about.
Imbalance drives large social systems rather than damaging them. Only 2% of users ever contribute, yet that is enough to create profound value for millions of users.
Most large social experiments are engines for harnessing inequality rather than limiting it.
Any measure of "average" participation becomes meaningless. There is a steep decline from a few wildly active participants to a large group of barely-active participants.
By definition, most participants are below average.
On Wikipedia, where there is no representative user, the habits of mind that come from thinking about averages are not merely useless, they're harmful. Instead, you have to change your focus to concentrate not on the individual users but on the behavior of the collective.
Once writers start getting more attention than they can return, they are forced into a width-versus-depth tradeoff. They can spend less time talking to everyone. (It's no accident we call these interactions shallow, and say that people who have them are strateched thin.) Alternatively, they can limit themselves to deeper interactions with a few people (in which case we call them cliquish or standoffish). At the extremes, they are forced to adopt both strategies, to limit both the number and the depth of interactions. A wedding reception is a localized version of this tradeoff. The bride and groom gather a room full of people they could talk to for hours, then talk to most of the guests for just a few minutes each so as not to be rude.
The coming change in group effort is on the ability to make nonfinancial motivations add up to something of global significance.
AOL's friendliness came from AOL's users, many of whom loved the service so much they worked as volunteer guides.
Evidence that enough people care about an article, and that they have both the will and tools to quickly defend it, has proven enough to demoralize most vandals.
Let the community do as much as they possibly can, but where they can't do the work on their own, add technological fixes.

Social awareness has 3 levels:
1. when everybody knows something
2. when everybody knows that everybody knows
3. when everybody knows that everybody knows that everybody knows

Now the highly motivated people can create a context more easily in which the barely motivated people can be effective without having to become activists themselves.

More wisdom about the participatory culture:
Our new freedoms are not without problems. It's not a revolution if nobody loses. Most obvious loss is to people whose jobs relied on solving a formerly hard problem.
The spread of cheap and widely available creative tools is sad for people in the advertising business in the same way that movable type was sad for scribes - the loss from this kind of change is real but limited, and is accompanied by a generally beneficial social change.
As the size of your network grows, your small-group pattern, where everyone connected to everyone, would first become impractical, then unbuildable.
Let the small groups connect tightly, and then you connect the groups. But you can't really connect groups - you connect people within groups. Instead of one loose group of 25, you have 5 tight groups of 5.
As long as a couple people in each small group know a couple people in other groups, you get the advantages of tight connection at the small scale and loose connection at the large scale. The network will be sparse, but efficient and robust.
Tie several few-person networks together into a network of networks.
It's not how many people you know - it's how many kinds.
A service business does best not by trying to do things on behalf of its users, but by providing a platform for them to do things for one another.
Failure is free, high-quality research, offering direct evidence of what works and what doesn't.
With low-enough barriers to participate, people are not just willing but eager to join together to try things, even if most of those things end up not working.
Linux got to be world-changingly good, not by promising to be great or by bringing paid developers together under the direction of some master plan, but by getting incrementally better, through voluntary contributions, one version at a time.
Linus Torvalds said, “I'd like to know what features most people would want. Any suggestions are welcome, but I won't promise I'll implement them.” This kind of openness is thekey to any project relying on peer production.
The number of people who are willing to start something is MUCH smaller than the number of people willing to contribute once someone else starts something.
Open systems lower the cost of failure. They do not create biases in favor of predictable but substandard outcomes, and they make it simpler to integrate the contributions of people who contribute only a single idea.
The overall effect of failure is its likelihood times its cost. Most organizations attempt to reduce the effect of failure by reducing its likelihood. Open source doesn't reduce the likelihood of failure, but it does reduce its cost.
Cheap failure, valueable as it is on its own, is also a key part of a more complex advantage : the exploration of multiple possibilities.
The resources invested in trying these actions will often cost more than the outcome. This in turn means there are many actions that might pay off but won't be tried, even for innovative firms, because their eventual success is not predictable enough.
It is this gap that distribution exploration takes advantage of : in a world where anyone can try anything, even the risky stuff can be tried eventually. If enough people are trying things, the happy accidents have a much higher chance of being discovered.

Also read
Lessons from Wikinomics
Lessons from Crowdsourcing
Lessons from The Long tail by Chris Anderson

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