The latest numbers have revealed that Wikipedia, the user-edited Web encyclopedia, gets more unique monthly visitors than the hugely popular video site YouTube. According to ComScore Media Metrix, Wikipedia sites had about 155 million unique visitors last month while YouTube's unique visitors were around 81 million. When I spoke to teen girls at the Texas Conference for Women, I asked how many of the teens in the room use Wikipedia for their homework. Every hand in the room shot up.

Teens love Wikipedia. Here's why: It almost always comes up in the top 5-10 search results in Google (which is where most teens begin their homework searches), and appears to have all of the information they are looking for. There has been a lot of debate over the accuracy of Wikipedia and where bias creeps in. Since anyone can edit the entries, people with a vested interest in how their company or their own profile shows up can and often do go in and edit.

The Chronicle of Higher Education recently published an article where one professor was suprised at how quickly errors he intentionally introduced to the site were corrected by its most active editors. There was also a recent article about the site in the New Yorker that's worth a read. The crux of the debate is really over who determines what's credible -- the gatekeepers in academia or anyone who just happens to be knowledgable. Whether or not you think Wikipedia is a credible source, you have to admit that it has evolved into a huge user-generated body of knowledge that's well, pretty awsome.

Frances Jacobson Harris, a high school librarian I interviewed for the book, told me when she is was teaching students about Wikipedia, she would point to someone in the room at a computer and say they could be editing an entry right now, she had her class look at the "history" of an article, which shows the IP addresses or nicknames of those who have edited it, and realized that the most recent edits were coming from her very own classroom. (see her comment below) What I tell teens is that Wikipedia is an amazing place to begin their research and get an overview, but that it's probably not the best reference material to source in a research paper. If there is a fact or assertion in a Wikipedia entry they want to use, try cross referencing it to find another credible source to back it up. The biggest challenge for teachers and librarians with Wikipedia is pushing students to go beyond what's easy, fast and almost always in their top 10 search results.