My advice for you would be to get by all means the 8800gts, be it BFG, XFX, Leadtek, EVGA or whatever, but grab the 640MB version...
It has already been proved that 320MB ddr3 could be insufficient for a mere 1280x1024 gameplay (high/ultra graphics that is)...check the Colin Mcrae Dirt demo...you need the bloody 8800gtx to run it smoothly...
I know it's just one example, and one on a dx9 game, not a dx10, so who knows what the future has in store for the little 320 MB sister...?
core2duo e6400
GA-P965-DS3
2 gb ddr2 Geil Ultra 800mhz cas4
XFX 8800 GTS 320MB
Arctic Cooler Freezer 7 pro
Hiper Power HPU-4S425-EU V1
Antec 900 (in a couple of weeks :d:d:d)