I'm trying to find a video clip of the Tuck Rule incident...
Just as an FYI, it appears that Oakland had the tuck rule called in their favor against the Titans once, and I know the Pats have had it called against them in a few games since then, too, so... for whatever that is worth :)
Ok, I'm watching it on DVD right now... slowing it down frame by frame...
The Tuck Rule states that both of the hands have to be on the ball in order for it to be a fumble (if both hands are on it, the ball is "tucked" so to speak). What I am seeing here is that Brady's left hand is not on the ball as he is being hit by Woodson. However, as Woodson is nailing Brady in the head with his forearm (which should have been a flag, by the way) his other hand is hitting the ball, pushing brady's right hand and the ball into Brady's free left hand - which was what jarred the ball loose...
Personally, I don't agree with the "tuck rule" - I think it's a bad rule, but it IS the rule, and it applied here. However, i would have been happier to see a flag with a 15-yard penalty and an automatic first down for the forearm to the head... ;)