You do know that the GTX 590 is getting very hard to find right?. It's essentially a Dual GTX 580 operating in SLI on a single card. As constepatdyak said, the GTX 680 performs at a similar level with a single GPU and at a very similar price.
Also, with Ivy Bridge you will be able to operate the GTX 680 in PCIe 3.0 mode because IB has PCIe 3.0 built into the CPU whereas the i7 2700K is a Sandy Bridge part and only supports PCIe 2.0. I'd wait a week and get a Ivy Bridge CPU and with any luck the GTX 680's might be starting to be available as well.