I have a GTX 295 and my concern is the implimentation of DX11. Everywhere I have read sais DX10 cards will run DX11 but I am concerned about limitations. DX11 hardware is suposed to come out 2nd half of 2009 so in not too long, you might not regret it to wait for a great DX11 card.
So my setup is a Q9550 and GTX 295, I "can" play FC2 maxed out settings and in some areas of the world the FPS does drop to where I go hmm the FPS could be a little better here, that game is made for the quad core as well and similar results of CPU usage as below, with the quad at about 60% to 80%.
I also have GTA IV, GTA IV is made for the quad core cpu, I had an E8400 before the Q9550 and I hooked up a second moniter to see how my CPU was doing the results were with the dual core both cores were completely at 100% constantly during gameplay and now with the quad it's at about 70% to 80%. The frames per second (FPS) are great though I am verry happy with the performance in that game and you definetly need at least 4 gigs of ram for that game.