I like Wiki, I really do...
At age 78, I thought I was beyond surprise or hurt at anything negative said about me. I was wrong. One sentence in the biography was true. I was Robert Kennedy's administrative assistant in the early 1960s. I also was his pallbearer. It was mind-boggling when my son, John Seigenthaler, journalist with NBC News, phoned later to say he found the same scurrilous text on Reference.com and Answers.com.
But I think they could be doing slightly more in the area of demanding personal responsibility from users. I think asking people to register with legitimate and possibly verifiable information (like ebay or paypal) might be a good start.
I also think that places like About.com that import stuff automatically from Wiki without bothering to check the veracity of a source that is always in flux, and so obviously questionable are IDIOTS.
Of course, that seems to be standard practice in the media now days. Back in the day, confirming information from a second source was SOP. Now days, one source will do. And it's OK if that source is another media outlet. "Fact checking" and "verification" really don't seem to be necessary today, which is a bit disturbing in a world where misinformation propigation and out-and-out lying are so ramped.
Yes, I understand one of the points of Wiki is quick editing by many people with many different specialties in order to get the most complete and accurate view of a society. But I also take it with a grain of salt. I go to it to build a frame of reference. Like, if someone says to me "I broke my suffelgesix." Wiki could give me a rough idea whether I should be looking for information on a body part, or a porcelin nicknack. But to quote it on a site that portrays itself as a "legitimate" information source, without investigating the veracity of said information? I think that's just damned irreponsible.
In summary: People are stupid.