I would suggest keep your current system, until AMD/ATI releases their R600 GPU's, and if you really want the "BEST" system, money can buy, if money's not an option, than I would suggest you to wait until AMD releases there new CPU's later this year, thats if they don't delay them again. But having a very fast Quad Core processor, and maybe two high end R600 GPU's, with atleast 2-4GB or RAM, you are looking at some serious power. It will even make the Xbox360 and PS3 look like a commodore 64.
But if your in a hurry, than i suppose you could get a core 2 duo, and two G80 GPU's. But I would say patience is worth it at the end.
But if your in a hurry, than i suppose you could get a core 2 duo, and two G80 GPU's. But I would say patience is worth it at the end.