I've always stuck with nvidia, no real reason other than it hasn't failed so far.
(except that one forceware release that caused massive overheats)
560ti is at least living up to the OC hype. I haven't felt the need to overclock yet, but I gave it a try now anyways. With just one press of a button:
Might even go higher if I raise the volts. Photobucket is quite terrible.
Oh, and since this topic was about Skyrim: