Yeah i've seen the same on live. Are you seeing this on PTR too? I think it was fixed with 7.0, because doesn't seem to be happening anymore with it at 60.
See a few posts above, it was the area I was testing in. I have disabled AA for the time being. There is a difference at 4K, but not a 20-30FPS worthy difference in certain zones.
I have also disabled vsync, triple buffering, and reduce input lag. I set FPS locking to 60 instead. Vsync was locking my FPS to 45 whenever I dipped below 60. I also set the game to Windowed (Fullscreen) to get rid of the tearing caused by no longer using vsync.
This was a pretty nice increase, getting about 50-60FPS flying around nagrand on the max preset (10).