Cat 12.11's even up performance, but at the same price I still think the 680 has the edge (mostly due to cooler, quieter and more efficient running).
Yeah, this is another important factor I suppose. From what I've heard the Nvidia 6-series cards are highly power efficient and that the 7970 is a bit power hungry when overclocked.
Also, just to let you all know, I really have 1440p in mind, so this is at higher resolutions we're talking about. I'm thinking the extra vram will be useful at 1440p?