I've been watching and using wikipedia for about a year now. I know there's been a lot of discussion on impriving wikipedia, and I would like to throw in my two cents.
I think it would improve wikipedia to allow forking of articles, and maintain these forks. Philosophically, I think postmodernism is mostly BS, but I think a postmodern critique of wikipedia would improve it.

- Wikipedia contains no authorship information. This creates a false sense of authority and objective knowledge. I find 'neutral point of view' to be an oxymoronic statement. A point of view is by defition a perspective; a bias.

- Contested truths are fought in a zero sum game where only one text can inhabit an article at any time.

So instead of 'the definitive' article, a 'contested tree' of an article.

Additionally, I recommend installing a 'signing off' system, where authors sign off on their works, perhaps using pgp keys. Users who sign a lot of articles in agreement with other signers get a higher reputation system. If someone updates a text, the text has a higher reputation if its ancestral authors sign off on the updates.

Filtering works by reputation would make a better wikipedia experience for casual users. Unpopular authors can maintain their own branches, and controversial topics might maintain several concurrent branches. This would relive edit wars as proponents of particular truths would be more intersted investing time and effort into crating and maintaining those truths than destroying others'. Furthermore, if someone's work is vandalised, in their perspective, that author can apply filters which ignore the updates of proponents of a competing truth.