Very true ilysaml, but he has the 550TI, which is a very different beast. The 550ti is like the 5770 in performance, and two in SLI won't be near the GTX580. One GTX560ti would probably be faster then two of his cards.
Brutal, if your system is good overall, I suggest getting the GTX560ti or the 6950. Both are great cards, though I'm not sure which plays BF3 best. They trade blows for the most part, you really can't go wrong with either one.