[In response to my post on Apple v. Does (O'Grady v. Superior Court) and Wikipedia, James S. Tyre sent me the following, which (with his permission), I'll make into a guest post.]
Without suggesting that citing to wikipedia is now fully accepted, O'Grady wasn't close to the first. The first that I know of (I've not researched it thoroughly) is:
We also reject the notion that the Department of Homeland Security's threat advisory level somehow justifies these searches. Although the threat level was "elevated" at the time of the protest, "[t]o date, the threat level has stood at yellow (elevated) for the majority of its time in existence. It has been raised to orange (high) six times." Wikipedia, Homeland Security Advisory System, available at http://en.wikipedia.org/wiki/Department_of_Homeland_Security_Advisory_System (last referenced Aug. 16, 2004). Given that we have been on "yellow alert" for over two and a half years now, we cannot consider this a particularly exceptional condition that warrants curtailment of constitutional rights. We cannot simply suspend or restrict civil liberties until the War on Terror is over, because the War on Terror is unlikely ever to be truly over. September 11, 2001, already a day of immeasurable tragedy, cannot be the day liberty perished in this country.
-- Bourgeois v. Peters, a 2004 decision from the (very conservative) Federal 11th Circ Court of Appeals.
I've seen at least 3 or 4 others as well.
James S. Tyre
[Sent later]
Bourgeois v. Peters, 387 F.3d 1303, 1312 (11th Cir. 2004)
http://caselaw.lp.findlaw.com/data2/circs/11th/0216886p.pdf
A problem with citing Wikipedia, other than the obvious "it's human-edited so it contains human errors" (which is true for pretty much every other source as well), is that you can edit the Wikipedia page you're citing *before* you're citing it to effectively construct any argument you want. If I want a Wikipedia citation saying "Seth has an IQ of only 89" then I can have it right now, by editing your page to my liking and then copying from the page before my edit gets reverted by a Wikipedian.