I have long advised my students not to cite Wikipedia as a source, and not to believe anything found therein without cross-checking other sources. After learning what I will relate to you below, I’ve revised that advice: Now I tell 'em, don’t go to Wikipedia at all.
(Disclosure of potential bias: I too have written paragraphs for Wikipedia on topics on which I’m an acknowledged expert – and returned later to see that some self-appointed guardian has removed most of it and, yes, crapped on the rest of it.)
This from the New York Times:
MONDAY, DECEMBER 5, 2005
NEW YORK According to Wikipedia, the online encyclopedia, John Seigenthaler is 78 years old and the former editor of The Tennessean in Nashville. But is that information, or anything else in Seigenthaler's biography, true?
The question arises because Seigenthaler recently read about himself on Wikipedia and was shocked to learn that he "was thought to have been directly involved in the Kennedy assassinations of both John and his brother Bobby."
"Nothing was ever proven," the biography added.
“The case,” the Times continued, “set off an extensive debate on the Internet over the value and
reliability of Wikipedia and, more broadly, over the nature of online information."
Mikayla Gilbreath was a 15 year-old jazz saxophonist and journalist when she became a a columnist for All About Jazz. She claims “jazz legend Sonny Rollins, international jazz star Candy Dulfer, and President of the Jazz Journalists Association Howard Mandel” as her mentors, and has interviewed sax legend David "Fathead" Newman. Mikayla and her performances have been profiled in AllAboutJazz.
The guardians of Wikipedia, hiding behind screen names and protected pages that prevented replies or queries to them, removed the article about Mikayla. Eventually a dialog ensued at the noted URL; Mikayla is “not famous enough”; “Wikipedia is not a place to ‘promote’ anyone or anything”; too much of the article seemed to be taken from a previously published magazine article.
As an interviewer, Mikayla seems to be the Larry King of the jazz world. As a musician, she tours nationally, has been covered in the press, and has enjoyed accolades from jazz cognoscenti – quite unusual for a 15-year-old. So much for ‘not famous enough.’
Wikipedia pages include articles on Moe's Southwest Grill (and the unrelated Mo's Restaurants), both mass-market chains that offer, I suppose, good food, but no other signs of distinction that would merit an encyclopedia entry. And there’s a very odd page of military market research, titled “List of Hawker Hurricane operators”. So much for ‘no promotion.’There may have been something to the copyright violation accusation. Then again, the articles were written by Mikayla’s grandfather. Gramps may have held onto the copyright, enabling him to use the material freely on Wikipedia. But the guardians didn’t bother to ask.
Wikipedia founder Jimmy Wales wrote, “People like us write Wikipedia…. We want to keep it growing… inviting participation from everyone.”
And then crapping on it.
An open-source encyclopedia is actually a fine idea. But Wales has not yet found the right model – the right set of rules and guidelines – to make such a thing work.
I hope a better model comes along, and when it does, it will recognize writers’ tendencies to want to “own” their articles. And their resulting habit, especially if they have too much time on their hands, of lurking on the wiki and erasing everyone else’s attempts to improve it.
 “Wikipedia: Open-source, and open to abuse.” By Katharine Q. Seelye The New York Times, December 5, 2005.