Tomas Haake of Meshuggah.
I think he's one of the best, if not the best metal drummer around.
He plays some jaw dropping beats. Check out Meshuggah's "Destroy Erase Improve" CD if you haven't already and you're into heavier some what technical music.
Sure there's more technical metal drummers out there. Sure there's faster metal drummers. But Tomas Haake is the total package and would have most drummers tied in a knot in little time.