Well, I'm the kind of guy that'll wait around for just about anything, just to get it cheaper. Keller, or at least the card you'll want, is out. I wouldn't wait for Ivy Bridge if you want to use it now. Sure, you'll get better performance, but you seem like the kind of guy that has enough money to buy a new CPU when you want to. Get the GTX 680, though. Wait around for Ivy if you feel for it, otherwise, do not.
I'm probably just gonna get the i5 for now then buy the ivy bridge.
Also, I've noticed that 680 has 1 GB less of gddr5 memory and is only 256 bit, what kind of difference does that make in games?