In light of the recent discussions here of Wikipedia, I’d like to throw in my two cents on the subject.
I like Wikipedia. In fact, I like it a lot. In fact, I have gone so far as to do what Eugene Volokh warned against — I’ve actually cited to Wikipedia. In fact, I cited to Wikipedia six times in a recently published law review article. (I’m not alone in this by any means–“wikipedia” gets over 200 hits on a Lexis search of law review articles, almost all of which are cites to entries.) In my case, I cited Wikipedia as a starting point for investigating personalities, such as John Mellencamp, Tom Clancy, and Marni Nixon. I’m aware that some of these entries contain certain inaccuracies, but I feel comfortable citing to them for reasons I’ll explain below. In the alternative, I suppose I could have cited to nothing (not very helpful to the reader) or cited to books (realistically, though, how many people would follow up on those cites?). Also, I should admit that, in part, I cite to Wikipedia sometimes because I hope some readers might take a look at Wikipedia and appreciate it for what it is. However, I’m not trying to deceive people about what Wikipedia is–it is, more or less, the Web, repackaged and reformatted.
In fact, before I cited to Wikipedia, I cited, on rare occasions and for very similar reasons, to web searches on Google for a specific term. (Again, I’m not alone in this, though the numbers of people who did this were smaller.) As far as I’m concerned, citing to a Wikipedia entry for Marni Nixon and a Google search for Marni Nixon are very nearly the same thing. Both are invitations to the reader to enter what you might call a “muddy information portal,” a messy and organic field of data that the citing author does not control, but feels would be helpful to the reader as a starting point for further research. Citing to something like that might be unorthodox, yes, but I don’t think it is beyond the pale.
To my mind, the difference between citing Wikipedia and citing a Web search is just a matter of the target’s format. When we search the Web, Google creates our “entry” on the fly with algorithms that prioritize popular and relevant websites. With Wikipedia, we have the dynamic of Web search somewhat inverted — creators with data they consider relevant to specific terms offer up that data to Wikipedia under a shared hosting umbrella in a common format (and with a commitment to collaboration). Due to this, Wikipedia entries generally look nicer. But other than that, Wikipedia and the World Wide Web are very nearly the same thing. Wikipedia’s openess, to both creation and revision, doesn’t guarantee much accuracy.