"Wikipedia is just the latest in a long line of encyclopedias. In fact, encyclopedias have been around in some form or another for 2,000 years. The oldest, Naturalis Historia, written by Pliny the Elder, is still in existence.
How do I know this? I looked it up on Wikipedia, of course. Is it true? Possibly. ..."
I'd say Wikipedia is far more accurate than not, but I would be suspicious of any descriptions of social phenomena or public figures -- especially if politics is involved.