Performance of the two is pretty similar, yet the 570 is now much cheaper. I was originally considering a 7870, but discounted 570's have piqued my interest. Also, there are several overclocked 570's available that should do better than a stock 7870. I'm using this with a 1920x1200 monitor. The 570 seems to have problems at higher res, and that's most likely because it's running out of memory. Would be nice if that point was noted in reviews, and it would partially explain some of the stuttering. Penny for your thoughts?
570 Cons:
less memory
heat
power consumption
Pros:
Cheaper
Overclocked editions
physx (meh)
cuda (somewhat useful)
7870 Pros:
Future proof
Cons:
cost