Some people, especially academics, are uncomfortable with Wikipedia as a "source" of knowledge. Notwithstanding the regulatory and control mechanisms to prevent "vandalism" of content, there is still skeptism among most academics about how far Wikipedia can be a trustworthy resource.
In COMMUNICATIONS OF THE ACM September 2007/Vol. 50, No. 9, Neil L. Waters explains "Why You Can’t Cite Wikipedia in My Class"
A recent post on SlashDot quotes another IT professor saying:
"People are unwittingly trusting the information they find on Wikipedia, yet experience has shown it can be wrong, incomplete, biased, or misleading"
There was an interesting case recently of a "circular reference" created by Wikipedia. "Ali G", claimed a wikipedia entry, had worked for Goldman Sachs. No sources were given. This found its way into a popular mainstream media journal and Wikipedia became a reference to itself!
Where does that leave us?
I'll leave you with a quote from http://tech.slashdot.org/comments.pl?sid=521670&cid=23103370 (reference link above)
The real Wiki-vandals are the companies, governments and lobby groups of all sorts that flood Wikipedia with their squeaky clean corporate profiles (yes, corporate governments), whipped straight from their websites … These entities are the true threat to the laudable goal of Wikipedia to provide a freely accessible forum for the production and storage of (hopefully well-referenced) articles for the masses and a forum that does not restrict the privilege of contribution to those that have jumped through the all the right hoops. … The printed word is no more reliable than the plasma. Lies may be propagated on Wikipedia, but not without debate. Politicians spouting their sludge find their propaganda sitting side-by-side with those that mock them… If knowing that anything in a Wikipedia article is as likely to be crap as correct, the average reader becomes more vigilant in clicking through to the supporting sources; then Wikipedia has served the purpose of bringing to the masses the healthy skepticism that is, after all, the cornerstone of all academic pursuits.Dark eyes look down from ivory towers. Do they cheer or do they fear?