Remember that the situation is not "OH NOES VAGUELY POSSIBLE (C) VIOLATION WE MUST FOLD TOMORROW!!1!" If you're talking about a possible battle, one should look to past battles, and particularly on contentious and politically charged issues like such an attack on Wikipedia would be.
It's worth considering that, as an academic work produced by a nonprofit, we have considerably greater scope for fair use. See the considerable quantities of quotes and fair use images in http://en.wikipedia.org/wiki/Xenu ? Not a squeak from the notoriously litigous Church of Scientology.
Furthermore, we have an active policy of aggressively removing copyright violations once notified, and even before being notified, which would get us many points in an actual courtroom. And the clock only starts ticking when you have been notified.
Furthermore, for the egregiously overbroad infringement suit Gregory Maxell hypothesises, the battle also goes out to the media. Imagine something more mediapathic. Suing cute fluffy kittens, perhaps? Not to mention that such a case would promptly bring to our aid ten thousand First Amendment ninja attack lawyers.
That is: we may well in fact be in a position to say "That's utter bullshit. Bring it on."
This is the reasoning behind [[Wikipedia:Avoid copyright paranoia]].
- d.