Hmm, thats stange, I tested the FEAR MP Demo, and CSS, and I notced low fps and shadow eff ups (in FEAR).
Bah, I'll wait until they go official. And yes, I think they are multi-threaded.
EDIT: I take it back, I had the 81.82 and that one sucked. The 81.26 however is really awesome! I did see a jump in FPS in most all games from 5-10 fps. Also, the link is right here: http://194.71.11.70/pub/games/PC/guru3d/nvidia/8126-whql-[Guru3D.com].exe