The obligatory link: Vermont college says history students may not cite Wikipedia as a source
Okay, I can understand why they did this. With a source as thorough as Wikipedia, both in its fact-checking, and its anti-vandalism efforts, if you don't write it out somewhere, it ends up being the only source you need, in many cases. In most cases, I'll trust it before I'll trust any other source of information on the web. That doesn't mean it's always right, of course, or that "doing your homework" on a topic shouldn't include a broader search of information, but Wiki has a solid reputation for a reason.
Well, they haven't written it off entirely. To wit, " History professor Neil Waters says Wikipedia is an ideal place to start research but an unacceptable way to end it. "
That said, I love my hive mind, and you're sure to see more of it in use here.