Do you have a triple display? No? Please don't speak for those of us who do have them, then.
The H test admitted that 4x MSAA crippled their tri-SLI 680 setup in BF3. If you want that level of MSAA (which not everyone wants), you need the 4GB VRAM edition to not run into VRAM walls with the 680, which changes price/perf. As much as 3GB VRAM is overkill for single displays, it allows breathing room you can't get at 2GB VRAM, and room to grow in case games of tomorrow require even more VRAM. FXAA is not MSAA. Say no to blur.
TR also did 5760x1200 testing and you can see their results here:
http://techreport.com/articles.x/22922/3
As for "modern games" I don't even know what you are talking about. BF3? You can't use only a few games as examples. Even NV themselves said, in their press release today, that the gtx 670 ties with the 7970 at 1920x1080 resolution across 25 popular games. Not beats--ties. At higher resolutions the 7970 will start to win, which is why AMD PR is desperately trying to get people to bench games at 2560x1600 instead of 1920x1080, when comparing the 670 to the 7970. (Good luck AMD, I have a feeling you already lost that battle.)
I think with equal pricing the 670 is a slightly better buy for those gaming w/ 1 monitor. For 3 though the 7970's extra VRAM and slightly better fps at high rez wins out. But price is not equal. They are changing though.