Yes, I also would recommend Nvidia SLI instead of Crossfire as of driver issues.
Also i7 for gaming rig is overkill I would suggest a i5-3570K. If you have no problem with budget then keep your i7 and also if you going for multithreading activities or other heavy professional work. For gaming 3570K and invest the remaining in a SSD. I think 128GB would suffice for Windows and some important games and applications.
So in all if you cut the i7(if only gaming) and invest in SSD would be more optimal.
It looks like overkill for a gaming rig. I hope you have monitors that will take advantage of the stuff you got listed.
I'd say that you may want to go with sli 670s vs the 7970s due to the driver issues amd has with CF "smoothness" in game play (CF cards can look more choppy in play but still have high FPS).
At this price range and no SSD? You got room in there to get one to have your rig boot up faster and have key games load faster.
thanks for the advice,
What size SSD should I get for the OS and maybe 1/2 of my favorite games?