The GTX 680 hasn't been relaesed just yet , though it should be tomorrow , and so there haven't been any benckmarks to look at and compare also the pricing is a guess at this point as well. Since the release is immenent you should wait and see what the benches are then you can make a better decision. The prices for the older cards are being lowered a bit and we should see what those bottom out at because there will be some good deals there. Right now you can get a GTX 580 for under $400 which the 580 is still a powerful card and will give great frame rates and game play. A 580 will still let you play BF3 on ultra and at 1080p.
I stopped using ATI GPUs years ago because of buggy drivers. I tried an AMD recently and it still had buggy drivers. Maybe I'll try another some day but why should I? I know everybody has driver bugs occasionally but ATI/AMD problems are the rule rather than the exception.