Help upgrading GPU for future

I was planning on upgrading my rig when the new AMD CPUs come out end of this year/next year however right now I have an opportunity to sell my vid cards (2x GTX 260 Core 216 SLI) to get new one(s), plus I am defenetely getting Battelfield 3 when it comes out in fall and my goal is to run it in full settings smooth. So right now I am looking for a single video card and then getting another one for Xfire/SLI in fall hopefully a notch down in price.

I know its hard to speculate as to what video cads will be able to handle a game like that but I need to try. Right now looking at 5870 because it is so cheep, can get one for $190, the next step up the GTX 560 SOC or 6950 2GB cost like $70 more (each!) but performance gain is marginal (maybe not so in SLI/Xfire?) So what do you think, will dual 5870s handle a brand new high graphics game like half a year from now? Any other suggestions/thoughts welcome.

Specs
1055T OCed @ 3.5Ghz
ASUS M4N72-E nForce 750a (will upgrade if needed for Xfire support)
8GB DDR2 RAM
2x monitors 1900x1200(gaming) + 1600x900 2ndary

Two GTX 260 is a lot faster than you think, especially when a GTX 460 at 900mhz is on par with a 800mhz GTX 560ti and both are slightly faster than a single gtx 285 depending on the clocks but are no replacement for two gtx 260. A single gtx 460 is enough to replace two meager 9800gt in sli with a margin left to be considered as an upgrade. The 560 ti will be slightly higher than that over all depending on the clocks.

You need to aim higher if you really want to upgrade.