Alex Soojung-Kim Pang points to a discussion on how visual depictions of the volatility of revisions to a wiki entry might be used to gauge veracity. Matt Jones surveys the discussion. Clay Shirky has an excellent piece on "authoritativeness." He says that Wikipedia has neither a personal reputation behind it ("the authority of, say, Coleridge’s encyclopedia was the original one: authority derived from the identity of the author") or commercial branded authority (like Britannica).
So, is Wikipedia authoritative? No, or at least not yet, because it has
neither the authority of the individual merchant or the commercial
brand. However, it does have something that neither mechanism offers,
which is a kind of market, where the investment is time and effort
rather than dollars and cents. This is like the eBay model, where
people you don’t know (no Mom’s Diner effect) can sell unbranded things
like art or one-of-a-kind clothes (no Levis effect). EBay can do this
because the syndication of user attention and the possibility of
recourse for bad behavior keeps people generally honest.