Upgrading GPU for 1440p Gaming

Hey guys, first post here.

I'm currently running just a single 6950 with 2 1080p monitors. I want to upgrade and get a 1440p monitor in between the 2 1080's, and flip them portrait. I dont really want to surround game on all of them, just on the 1440p and use the other 2 for whatever (itunes, stream chat, what have you.)

In order to do this, a GPU upgrade is in order. I've been looking at crossfiring 7970's, Running 670's in SLI, maybe a 780, or perhaps waiting to see how the AMD 9000 series turns out. I'd really appreciate some feedback, as i'm not too familiar with the 1440p capabilities of cards, nor do i know any rumors/supposed specs of the 9000 series.

I should also clarify my budget - i've got about 800 dollars to spend on the cards. A nice budget to have :D

Thanks a ton!

I would go with a 79xx card, or Nvidia 700 series: 770 or greater. 780 is pretty balanced with 1440p.