I think that
http://en.wikipedia.org/wiki/Lame_edit_wars is worth a look. Personally, for the humour value, but if you're a Wiki-detractor then it's something you could seriously use as an argument as well.
Incorrect, vandalised or downright hoaxed information that stays uncaught (ISTR once editing and/or reverting a page claiming that Europe[1] was on Mars) is definitely a problem, but if you Google something that you know a little about and find a standard web-site that encapsulates the required information but is blatantly incorrect in some way then you have no real recourse. There's also no real way to be able to convey your sense of foreboding to any future reader of that Googled-for page's inaccuracies, never mind actively qualify half-arsed explanations that don't really do the subject justice, etc...
Wikis do solve these other problems. But at the expense of "equal and opposite experts" battling it out when it isn't clear-cut. Sometimes it's over terminologies, interpretations or semantics, sometimes even over more trivial things such as UK/US English variations (e.g. "Orange (Colo{u}r)"). Being inadvertently caught within the cycle of change-and-revert-and-unrevert-and-rechange cycle (at least taking an interpretation as gospel, and basing upon that your future acceptance of other sources) is probably the biggest trap you can fall into. IMO.
As to the whole subject of
citing Wiki, as opposed to its usefulness in general (and, indeed, launchpadding) reference, I wouldn't. But there are plenty of ways to qualify your references to at least give the same "Caveat Emptor"[2] to your readership that one should personally have taken account of in the first place...
[1] It wasn't
the page on Europe, but something that located the subject as being in Europe, which was "a continent on Mars" or similar.
[2] Or, as I have heard it rephrased, for the web: "Caveat Browsor"