I think you are not sorting through the pricing in your own links. Every cheap pricing for 7970 is the regular version. Ghz editions are priced very close to 680 (like $30 ~ $50 difference?). Few 680 are priced ridiculously but we are not arguing about whether there are outliers towards high pricing point.
You just can't take the most offending pricing 680 (mostly EVGA), compare it with 7970 price, then bring in 7970 Ghz edition performance to claim complete wipeout victory for the AMD. In a way you can physically do that, but wouldn't make it so.
You're not getting it, are you? One or two of those cards are reference (normal) designs. Stuff like the Vapor-X or Windforce 3X are some of the most legendary coolers out there, and they are GHz editions. I'm not sorting through my pricing because I really have no need to - it speaks for itself. Did you know when my friend bought his Lighting 7970 the closest thing at that pricepoint to it on the green team was an upper end 670? My original point about the GHz edition cards is that they are no more expensive than an ordinary card - and if they are, like mine was, then there's probably a reason (best air cooler available currently) and even then you're only just scratching the prices of the 680s that can actually match up in pedigree. I'm rolling Matrix RoG, at that pricepoint you're rolling stock designs. Even then, 7970s are phenomenal overclockers - stick the core clock to 1GHz in MSI Afterburner, crank up the voltage a wee bit if need be, adjust the fan curve - boom. GHz edition performance. I'll say again, I'm not looking for the most expensive 680, I'm trying to show you that pretty much any 680 is monstrously and unjustifiably more expensive (and basic, worse performing etc.) while the 7970s are better performing, higher grade etc. etc. and much cheaper, usually by about £100