ATI > NVidia.
just saying that from experience the ati cards last longer and they support more software changes. ATI has already got support from some game makers who are making games for direct X 10.1 ... its the red tide, get an ATI card. dual 4870x2's would be nice haha but i went with the 4850 cause its cheap and has the highest performance/price ratio in the market. i dont really care about all that, it just plays all my games on highest settings lol
i figure when they come out with something new the dual 4870x2's will have seemed like a waste of money, whereas i only spent like $160 on my card so i won't regret it lol