Title says it all.
Nope.
Hmmm, so wouldi t be a good idea to sell them both and get a better card with more Vram.
What kind of budget do you have?
Even if dual 7850s can't run 1440p 60fps, its sub $300 on newegg. In my opinion, get a 7970 which is around $300.
6970 xfire can handle, dont worry, it will work. Be prepard to use low on really demanding games. It should be playable. Worst case scenario you turn the rez to 1080p on the game you cant run and run everything else at 1440p.
6970s overclocked really high in  xfire are the equivalent to 7850 overclocked xfire or 7870ghz xfire depending on the situation, games, and overclocks
dude 6970 crossfire = $600 while 7850 crossfire = $300
I'm not sure how reliable these benchmarks are, but it's the only ones that I could find that tested multiple resolutions with 7850s in crossfire.
Based on these benchmarks, two 7850s could easily handle most games at 1440p with mostly high-ultra settings.
You'll be fine. I have a 7970 with a slight oc that can run bf3 and moded skyrim 1440p at around 60 average fps and two 7850 should be similar in performance. You can also turn of AA because it wont do you much good at that high a resolution. Stick with what you have because theres no point in investing in a 7970 when you get roughly the same performance. You would probably want to upgrade to a 780 or amd 9xxx series sometime in the future though.
I was thinking that but i wasn't sure. I did see benchmarks for 2 Radeon 7850's at 1080p BF3 113fps avg. This obviously wont be ta same for multiplayer + 1440p i think it would maybe half the framrate (maximum effect.)