lbgsloan, Crysis is quite well optimized. Even though it's slightly old now, it's still probably the most advanced game engine out there (mainly because Crytek the company really likes making engines, and they chose to target PC only).
By the way, your info is out of date. I have a single Radeon 5850 running it on all Enthusiast (1920x1200) at about 40 fps, which is very playable.
Thread is slightly old, but:
There is not a Gaming rig I know of that can run Crisis with DX10, Ultra Details, at 2560x1600 with 4 or 8x AA and everything else turned on.
I have a 4ghz i7 930, 6gbs of RAM and 2 xfired 5870s, they can't even do it. Maybe 2 OCed 5970s, but at that point its not worth it.
Crisis wasn't designed to run at those settings, just for screenshots to be oogled over. Think about it, it was released back during the 8800 days, that was 3 generations ago and it still can't be maxed out. Crisis 2 will probably be that same