Thanks all, for your input -- I appreciate the support and ideas. And I agree that balancing free expression with the "community" spirit of a forum is not an easy endeavor, requiring a high degree of diplomacy in order to build a constructive web community or portal that doesn't alienate constructive contributors.
My wife moderates a not-for-profit forum for parents of kids with speech problems. I've learned a lot from peering over here shoulder now and then. You'd think that such a forum would be civil and constructive -- but not so. I cannot believe some of the stuff she's forced to "not post".
It's not the heated discussions that are the problems (although they often precipitate problems)-- rather, the problems can be grouped into three constants: irrelevant or off-topic posts, someone trying to sell something or posting with a hidden commercial agenda, and the most common reason: disrespect for others. So I agree, moderation is a necessary evil. (I cannot understand why audioreview does not remove clearly ridiculous ratings that taint an otherwise well regarded product and detract from the overall usefulness of their site).
Although I don't take quite as extreme position as Brianw above, his point of monikers certainly has caused me to rethink my position.
I never really understood monikers -- do they do more harm than good? I'm not sure. On the one hand, they protect privacy and can even be descriptive. But too many people hide behind them and launch attacks from within their "shell". And my own experience is that using your real name builds credibility -- I think it definitely helped me sell more for higher prices on eBay.
What do you think about monikers?