Wikipedia will celebrate its tenth birthday at the end of this week. It's one of those anniversaries, like the recent twentieth anniversary of the Internet , that makes you realize how ubiquitous a particular tool has become.
It was only a few years ago that we had a lively faculty brown bag lunch discussion focused on "what the heck do we do about Wikipedia?" Faculty were concerned that students were relying on an intrinsically unreliable source, that they weren't willing to go beyond the easy and obvious, that they were losing respect for expertise and authority. Those faculty who weren't personally familiar with Wikipedia worried it was full of hoaxes and lies; those who used it regularly were nevertheless perturbed that students used it just as often. The very nature of knowledge seemed threatened by the free-wheeling "anyone can edit" nature of a wiki. In the past few years, though, people seem less likely to attribute students' love of online shortcuts or inability to distinguish good sources from bad as "the Wikipedia problem." Wikipedia has matured, and so has our familiarity with the read/write nature of online knowledge. Either that, or our students' habit of citing really terrible Websites has displaced the blame from Wikipedia.
Over the years, I've come to appreciate the way that Wikipedia in so many ways helps students understand fundamental features of how information works. I have always struggled to get undergraduates to pay attention to cited works as leads to valuable sources. They think of references as fine print, as the ingredient label that is mandated by law but not really important enough to photocopy. Though they have worked hard to format references themselves, they are confounded by trying to read them. "Is this a ... book? or a journal, or ... anyway, what am I supposed to do with this?" The act of tracing ideas through citations does not come naturally to students, and locating a known item not discovered through a keyword search of a database requires recognizing things such as journal titles or how to tell an article published in a journal from an essay published in an edited book.
That's still challenging, but in the past couple of years, I'm seeing students volunteer that tracing citations is a useful research strategy. Whenever I pull up a Wikipedia entry during a library session, at least one of the students will point out the references at the end of the article and suggest that they might be worth pursuing. They finally seem to get it: those are leads, and were selected because they are particularly valuable ones.
Students also seem a little more savvy than they were about the rhetorical act of choosing sources for a purpose. Most of the recognize that Wikipedia, thought possibly their first port of call, is not going to impress their teacher. They realize that the authority - the dignity - of a source matters. That doesn't stop them citing high school projects from Knowledge Quest or treating an Australian tour company as an authority on Aboriginal culture. (Yes, I got both of those in papers last fall.) But at least they get it when you point out that a source from a recognizable expert carries more clout. They've already encountered that peculiar bias when it comes to Wikipedia.
Wikipedia also demonstrates that knowledge itself is a community project, one built socially by people adding information, querying that which they find dubious, and revising over time. Unlike traditional general encyclopedias, you can view the changes and go behind the scenes to see how disputes play out. Though Wikipedia's culture is pre-postmodern enough to urge contributors to adopt a "neutral point of view" (how quaint!), in many ways it mirrors the free flow of disinterested ideas that build scholarship. Students can see that knowledge is built, not produced in some remote factory and delivered fully assembled.
Finally, Wikipedia makes it clear that knowledge isn't just for school. It's remarkable that volunteers take the time to contribute, shape, and polish articles in order to explain everything from the 1928 Okeechobee hurricane  to the development of and cultural allusions in the Okami video game (an article with 144 references - now that's some serious fine print). Like much of scholarship, this is a big thing done not for money, but for its own sake, a project that will never end, that has no purpose other than to gather and share information freely. It should help students recognize that being on the test is not the ultimate measure of importance, that lifelong learning is more than just a slogan used in college mission statements. Hey, it even has its own Wikipedia article. 
So happy birthday, Wikipedia. We know you aren't perfect, but we can work on that.