I have no idea what techniques the CIA uses, but biometric analysis isn't inherently unbelievable.
That doesn't mean that that particular report was true -- plus, that report didn't even include any evidence that Saddam Hussein had been killed.
I still think that Hussein is alive, because of the political stability we're seeing in Iraq in spite of the great stress it is being subjected to, and because of the nature of the videotapes showing him.
I also think that there is no way of distinguishing between information and disinformation in this war, and I'm withholding judgment on the truth of virtually everything I hear, especially (but not solely) isolated, unsubstantiated reports.