So any other input? I'm going to be either picking up the 280x or replacing it for the 680 Power Edition in the next hour. The price is good on both so that doesn't make a difference (680 is ~£230 and the 280x is ~£250).
If I could see into the future to find out only one thing right now, I would completely waste it on seeing if 3GB will be needed in the next 2 years for 1920x1080 haha.
I would stick to your original order unless it bugs you that much. Go with your gut. The 680 is still a great card though and if you really want, you can unlock the 1.212v. The 7970/770/680 are all so close in performance, just pick the one you like most.
My 770 handled bf4 beta ultra easily, basically a 680, I will say memory was at 1900mb but you know as drivers and the game matures it will probably manage memory better too. All I know is my average fps was in the 70s using fraps on 64p matches, not as high as my normal 100-120fps in bf3 but its beta after all.