Sometimes i kinda miss the point of this thread, even when the sys specs will be released, nothing is nailed down. Specs are just an approximation on how u should expect your game will run on your pc. If you have the exact specs or exceed them, doesnt mean that the game will run like on ice.
Many other factors involve, like max, avg, low fps. Fps in certain areas, config of graphics, tweaks, OC on rig, same rigs, different results, different OS, how the individual is satisfied with his fps (some like above 60 fps all times, some like only ultra graphics, some are used to lower fps, some want solid fps), so, many many factors.
Sys req, when they will be released will be just a small start point, on what to expect, expect is big talk, specs dont reflect entirely on the game.
Some specs based on fps on 1080p and other resolutions could be nice, but no company has done such thing.
And for the specs, i still believe on the recommended side will be written a gtx680, as recommended (this doesnt mean that it will run smooth on a 680). But i think either a gtx 680/770(same card) or a gtx 760 will be written on the recommended area of system specs, when they will be released, my predict for people who want the name of the card written on recommended area of specs.
I dont expect to be a gtx 780, because if that, the game will run much slower than anyone has thought.