Here are some new resources that can help to explain Wikipedia to skeptical colleagues. As I have written in earlier posts (Wikipedia goes undercover, Wikipedia again), there is considerable resistance to Wikipedia amongst teachers both in schools and universities. Students are advised not to use Wikipedia as a source in their work on the grounds that it is not academically reliable.
There is now a very useful page on WikiMedia Outreach, FAQ for librarians, that answers many common complaints about Wikipedia. For example:
How common are mistakes on Wikipedia?
Because Wikipedia is editable by anyone, we can't guarantee you won't stumble across a mistake; you may. But mistakes are fairly rare: external studies have suggested they occur at about the same rate they do in traditional encyclopedias. One thing that's great about Wikipedia is that it allows anyone to correct a mistake. So where a printed encyclopedia will need to wait for its next edition, for a mistake to be fixed - on Wikipedia a mistake can be fixed instantly, and often is.
Another useful source of ideas is Wikipedia in the classroom: Tips for effective use on Faculty Focus which, for example, recommends students writing new Wikipedia articles as written assignments.
Finally a new video from those wonderful people at Common Craft called Wikipedia: Verifiability and Neutral Point of View.