don't have evidence but they
claim to have evidence confirming his identity to a very high degree of probability, including DNA, facial recognition, and eyewitness testimony, according to this article: http://www.freep.com/article/20110505/N ... |FRONTPAGE
As far as I know, Al Qaeda hasn't disputed the claim that he was killed. Of course, that is merely suggestive. It occurs to me that, if he was still alive, he and his circle might be pleased to let the world think that he was dead -- at least for now.
However, the official story doesn't seem to me to be particularly unlikely.