Look at the standard of the games the 680 wins in though Greg, they're all rubbish Lol. Even so some of the fps figures in those graphs you keep quoting are at odd with what i see on other sites plus there's a fair few decent games missing from that. I don't believe you can argue the 680 is equal to a 7970ghz edition.
Taken from Anand, a well trusted site.
"Looking first at NVIDIA’s product line, Titan is anywhere between 33% and 54% faster than the GTX 680. In fact with the exception of Hitman: Absolution, a somewhat CPU-bound benchmark, Titan’s performance relative to the GTX 680 is actually very consistent at a narrow 45%-55% range."
"Moving on, while Titan offers a very consistent performance advantage over the architecturally similar GTX 680, it’s quite a different story when compared to AMD’s fastest single-GPU product, the Radeon HD 7970 GHz Edition. As we’ve seen time and time again this generation, the difference in performance between AMD and NVIDIA GPUs not only varies with the test and settings, but dramatically so. As a result Titan is anywhere between being merely equal to the 7970GE to being nearly a generation ahead of it."
"At the low-end of the scale we have DiRT: Showdown, where Titan’s lead is less than 3%. At the other end is Total War: Shogun 2, where Titan is a good 62% faster than the 7970GE. The average gain over the 7970GE is almost right in the middle at 34%, reflecting a mix of games where the two are close, the two are far, and the two are anywhere in between. With recent driver advancements having helped the 7970GE pull ahead of the GTX 680, NVIDIA had to work harder to take back their lead and to do so in an concrete manner."
If you want to play the latest and greatest dx11 capable games the 7970 offers much better performance and even more so as the res increases. If you like playing world of warcraft at 1600p go for a 680 Lol.
7970Ghz % Faster at 1440p - Gap will increase at 1600p
dirt - 44%
total war shogun 2 - 12%
hitman - 16%
sleeping dogs - 32%
crysis - 33%
farcry 3 - 3% faster