I have a legit copy through the EA downloader; I'm not hinting at what the OP is running, just noting it.
I just played through the entire game today, on my sig rig. Everything's been OC'd. I also forced the maximum settings through the Nvidia CP (including replacing the in-game Vsync with the CP Vsync to get rid of the floaty controls and get a proper framerate).
I didn't crash at all. The only problem I ran into was that a portion of a level failed to load after exiting an elevator, but that was fixed by going back up the elevator and coming back down. I didn't experience any glitches beyond that.
It seems that any problems people are reporting are either from cracked copies, or very isolated scenarios.
EDIT: I'm going to just chime in and say there's probably no fix for it. If you're running a legit copy, try a re-install of the game. Make sure you back up your save data if you do so.
Edited by EfemaN - 1/30/11 at 2:42am