Got two copies of this game for X-Mas. It plays rather well on my rig at the following settings:
1280x800 (maintaining 16:10 aspect ration for best scaling)
All in-game options set to "High".
I can tell in a few places it'll dip to the very low 20s or maybe lower. But it's never for more than a second or so. For the most part it always remains very playable.
Anyhow, I'll probably get an 8600GTS for the computer that is using my second 8800GTS. Then once that 8600GTS arrives I'll try SLi with my 8800s and see if that helps my framerate any.
Oh, I'm playing the 64-bit DX10 version.