I'm very disappointed in Crysis. I played for about an hour last night, 55 mins of that time was spent playing with settings to try to get it to look DECENT and maintain at least ~30 fps... I couldn't. I looked at all the tweak guides. I think the settings I ended up with was 1280 x 800, no AA, shader quality on high and everything else on medium and water on low. I believe I'm up around 40 fps but it simply does not look impressive AT ALL.
Call of Duty 4 on the other hand I can run on ALL of the highest settings, looks amazing and multiplayer runs as smooth as can be.
The only good thing I can say about Crysis is that you can definitely see there is a lot of technology and potential and interactive qualities to the graphics and terrain... but, its just NOT worth it at this point.
AMD X2 6000+
eVGA 8800 GT
4 gigs Corsair DDR2
470 PC Power & Cooling PSU
22" Dell LCD