I agree that pseudonymity and anonymity are two different things, and the article is interesting. However, I think the main snag comes with source verification. It's easy to say that you can look at someone's track record, but that does require you to have a certain level of expertise.

For instance, someone told me a while back that there are some Hebrew words in the Old Testament which don't appear anywhere else, so any translation is going to be pretty much a guess based on context. I don't know any Hebrew, so this could be completely wrong, but I believe him because he has a PhD in Theology. However, what happens if someone on Wikipedia makes a similar claim? I could examine their history of edits, and see that they've made lots of other comments about Hebrew, but that won't tell me whether any of those edits are correct. It would help if I could rely on their credentials, but then you wind up with someone like Essjay, who falsely claimed to be a professor with two doctorates.

It doesn't bother me if you want to use a pseudonym on LJ, but that's because I know you; in fact, I know the real names of everyone on my friends list, and I don't see that ever changing.