There has been phenomenal debate around the worth of Wikipedia, and most of the key elements of the debate can be found on Wikipedia itself. Indeed, in one of its own articles, Wikipedia itself notes that
Wikipedia acknowledges that it should not be used as a primary source for serious research.
but its value as an encyclopedia for me is endless. There is no way I could have written a thesis on the use of social media had I not had access to the definitions therein. Current information on the the terminology used in the area of social software use just wasn't available to me in books, and relevant peer reviewed articles were few and far between, in obtuse articles not held by my university.
Barry Leiba reviews research papers, and has kindly cited some examples of where Wikipedia shouldn't be used in research papers. His greatest bugbear appears to be the fact that references cited may have changed by the time the reviewer checks the reference, which is fair comment. This is mitigated however by refering to the precise version. David Gerard's comment on the same post explains how -
Click on the "History" tab and you'll see every version inthe edit history. Whereas the version at http://en.wikipedia.org/wiki/Inflation may change, the version at http://en.wikipedia.org/w/index.php?title=Inflation&oldid=162022107 (14:46
UTC, 3 October 2007) will not.
Wikipedia are attempting to get around the problem of peer review, with, suprise suprise, a peer review system...based on "trusted" sources. To earn this trusted status, users will have to show some commitment to Wikipedia, by, for instance, making 30 edits in 30 days.
This seems very much a quantity over quality strategy, but I'm sure its more robust than that (!). New software will also be used to give a "trust score" to contributors based on whether their edits are changed or not. This means that any topic in which there is healthy debate and disagreement will therefore be a no go as edits and changes will reduce trust scores.
In terms of academically accepted definitions, maybe the solution is for the Oxford English dictionary say, to produce a free online dictionary which takes contributions from us mere online mortals, to speed up the process of adding new words. As it is, you have to subscribe to even view the Oxford English dictionary, it takes an age for new words to be included, and right now, there's just no real substitue for Wikipedia.