Gene Weingarten, a humor writer for the Washington Post, has a piece titled "The joys of writing your own Wiki-bio" (carried by several other papers, including the National Post here in Canada) . In this article he describes a series of edits he made to his own biography on Wikipedia, testing whether the fact police of Wikipedia -- a nebulous group of usually young males with an excess of free time -- would catch and retract his distortions.
He was creating a "Wikiality".
We don't have to take his word for it -- look at the edits yourself (Gene's edits are apparently the ones coming from 69.255.218.128 - he didn't set up an account, or attempt to create even a cursory history of credibility). While Gene starts off small, he very quickly resorts to making outrageous claims.
By the end of his experiment, he had made a string of absurd changes, including "In 1984 and again in 1986, Weingarten competed in the Alaskan Iditarod, each time assembling a team of mongrel dogs rescued from local shelters, and one very large house cat. He finished third and sixth, respectively.".
27 hours later, a Wikipedia defender reverted his vandalism. Seeing even the last edit, it was painfully apparent that it was vandalism, so they just reverted back prior to that user's string of alterations.
Gene ends off his article with the paragraph "All in all, the system worked. I'm impressed, and a little disappointed. There was more that I wanted my biography to say."
Gene is hardly the first to perform such an experiment, distorting Wikipedia with outrageous (or widely publicized, as in the Stephen Colbert episode) changes, then declaring that the "system works", and that the wisdom of crowds concept has been proven out.
This has proven nothing of the sort.
In essence it's a TSA inspector declaring that homeland security works because they couldn't carry a poseidon missle on their shoulders through airport security. Using examples like this for a sense of security, or accuracy, is grotesquely misleading.