The previous thread about Wikipedia is now locked, so I'm posting separately to make sure I reach all the DU members who had so much fun vandalizing the Wikipedia article about the tsunami.
Wikipedia has an article about DU (<
http://en.wikipedia.org/wiki/Democratic_Underground>). Someone edited the article to add a mention of how some DU members had vandalized Wikipedia (<
http://en.wikipedia.org/w/index.php?title=Democratic_Underground&diff=9596123&oldid=9595462>). I've reverted that edit, because I think it was a minor incident that doesn't merit inclusion in a summary article about DU. Just remember, though, that when you act in such an infantile fashion, you're handing people a stick and inviting them to beat you with it.
On the general question of Wikipedia's reliability: Yes, anyone can come along and change the article to say that the tsunami occurred in 2304 or 1812 or whatever. Anyone else can come along and change it back, though. There are people who are genuinely interested in working together, without being paid, to produce a valuable resource that's available to all Internet users without charge (and without advertising and without paid links). There are other people who want to push a particular agenda or who just want to amuse themselves by introducing errors. Wikipedia is an experiment, testing the theory that the sincere contributors will outnumber, and will fix the problems created by, the others.
Yes, there are right-wingers on Wikipedia. For example, one of them made this edit: <
http://en.wikipedia.org/w/index.php?title=George_W._Bush&diff=9560533&oldid=9557683> to the article on Bush to remove most of the unflattering information. (The left column shows the affected passages of the former version; the right column is the new version.) The information has since been restored, though.
The fact is that people are using Wikipedia. According to Alexa, it's one of the 200 most-visited sites on the Web. <
http://www.alexa.com/data/details/traffic_details?q=&url=wikipedia.org> That's not bad for a bunch of volunteers who have to scrounge for donations to buy servers.
I wish more progressives would contribute, in a constructive way, to Wikipedia. There's a lot of valuable work that can be done even within the constraints of the site's "Neutral Point of View" policy. If you choose not to spend time improving Wikipedia, though, at least don't mess it up.