Ano, pseudo ... what's the best 'nymity?

There's an ongoing conversation in online news circles about identity and community. Vin Crosbie's distinction between anonymity and pseudonymity is a good one. I think there actually are five identity models that I've experienced:

1. Real, verified, published names. I first encountered this when working with Ziff-Davis Interchange. Under the Interchange model, publishers (such as Star Tribune Online and the Washington Post Digital Ink) operated their own paid-access services charged on credit cards, so the names were genuine. The discussion quality was first-class and behavior was sterling.
2. Real names required but not verified. When we moved the Star Tribune's online operation to the Web, we transported the existing discussion culture and rules -- but we had no method for enforcing the real-name rule. Periodically we'd have incidents, but overall the conversational quality level was maintained. (The biggest incident came when Salon booted a long list of troublemakers, who discovered the Star Tribune was running similar software. It was like an plague of locusts, but the local culture eventually prevailed.)
3. Pseudonyms allowed, tied to unpublished real names. This is the model we selected for BlufftonToday.com, and I think it's an excellent compromise. Our goal was to get broad participation, and this model helps protect participants from offline harassment and stalkers. The site has been extraordinarily successful with women in that hard-to-reach 24-40 segment. Most participants use pseudonyms (some even blog using the identity of their pets), but some prefer to display their real names. Staffers use real names.
4. Pseudonyms allowed with complete anonymity. This is the model that was in place at most Morris newspapers when I arrived, and the model that existed at Cox when I was there. There is some "reputation management" effect even with pseudonyms, but overall those systems tend to be dominated by a small number of users, generally men, who often are aggressive and occasionally abusive in their behavior.
5. Completely open systems -- post under any name you want (or in Slashdot's case as "Anonymous Coward"). In my experience this almost always leads to rampant abuse. There are ways of applying community moderation (Slashdot's system is an example) that pushes morons and trolls into the background, but I generally wouldn't recommend this model to anyone seeking to build local community. In addition to the interpersonal abuse problem, open systems recently have been overrun by spam.

I think identity has a powerful affect on the quality of conversation, but it is not by any means the only powerful factor. Clear goals, clear rules, visible staff participation and leadership, and consistent oversight/management are equally important factors that have nothing to do with technology and are all too frequently overlooked. I have seen many well-led anonymous systems with both high participation and good behavior.

There is one other model that I occasionally encounter: enforced pre-publication review. I don't know of a single site that has been able to build a positive interactive environment while requiring contributors to submit their postings for editorial review before they are published. The model simply doesn't work. I still occasionally encounter a dinosaur editor who thinks it's a good idea. I usually manage to bring him around with some legal liability arguments. What really bothers me about the whole idea is the disrespect and distrust of the community that it reveals.