Well, I have an i5 2500k, gtx 670 and 8GB RAM. I get pretty much a consistent 60 FPS, but it'll stutter at the worst possible moments for no reason. Walking around some random corridor? A sudden .5 second stutter. Enemy just about to attack? A sudden .5 second stutter (not nearly with every enemy and isn't dependent on whether it's inside or outside. Just happens randomly).
I've asked people in the GAF OT and was basically told "It's an unoptimized p.o.s. I have way better specs and it still randomly stutters as well.
It's not even that my settings are too high or anything, as everything aside from those stutter moments play at a consistent 60FPS. Seems like it'll occasionally just rising tackle CPU usage for no raisin.