Over and over, Web 2.0 proponents stressed the importance of allowing the highest degree of free expression. Each credited the bulk of Web 2.0's value with the results of openness and acceptance. That doesn't mean that you cannot set parameters, but be cautious about setting them too narrowly or you risk choking off creativity and other gains.

"You may ask, 'But what if community says bad things about our products?'" says John Hagel, longtime Web 2.0 consultant and chairman of an upcoming Deloitte research center on Web 2.0 and other technologies. Remember that the watercooler conversations are going to happen whether you listen or not, he says. "The only choice you have is whether you will participate." Through listening and participating in conversations comes value, the more participation the better. Even if what you hear hurts. "I think most companies today are still putting boundaries too narrow relative to where value exists."

Set Reasonable Limits. That's not to say that no parameters whatsoever should be set. Behenna, Hagel and others point out that rules of reason still apply—no lawbreaking, confidentiality breaches, and so on—but they believe most risks tend to resolve themselves. "A lot of potential risks get managed by people," says Hagel. "You need moderators, policies and rules, but start with a limited set of policies rather than try to anticipate every risk."

And this may take time to figure out. Dietz says that Dell is still determining just where the balance between openness and moderating is, but says that "all of the [deleted comments] have been related to content that was vulgar, obscene or threatening. "With folks who rant," Dell may actually reach out and see if it can fix the problem. But for the most part it's comfortable leaving rants there because the community tends to take care of them, she says.

Still, there are ways to encourage civility. Marino recommends having a clear code of conduct to set the tone. When signing up, members must check off that they will abide by the CarSpace Member Agreement, part of which clearly outlines expected member conduct. Says Marino, "We have a very clear membership agreement that tells them what's OK." And like encourages like. "If you move to a nice neighborhood you're inclined to keep it nice," she says.