You know, I wonder if you can cite specific examples of what people say on Internet forums -- there's MLA citations that can be applied to that sort of thing IIRC. Based on concrete examples, you could make inferences about trends or something. But then again, it's hard to say anything in general about Internet behavior because there's infinite variety.
What really strikes me about Internet behavior is how honest people are sometimes -- we express things we might not normally in real life. For example, people feel no qualms about discussing personal dilemmas in the Frustration Thread. Some users have problems with siblings, some with their bosses, others with Bob the tow trucker, etc., etc. What is it about anonymity that makes us feel so open and willing to be honest?
However, we're not really anonymous after all, are we? As with any community, the Compendium consists of people brought together by common interests, and we feel just as strong about the friendships we make here as the ones we make in real life sometimes.
In any case, I guess what I'm trying to say is that Internet forums are ripe with opportunities to conduct first-hand research on human behavior. It's like having millions of open diaries right at your fingertips.