Not long to wait for the 4gb models, take a look here:
http://www.overclockers.co.uk/productlist.php?groupid=701&catid=1914&subid=2255&sortby=priceDesc
I game at 2560x1440 with 680GTX 2Gb and never had any problems with fps unless I max...
Already got mine! Asrock z77 extreme 6 , the board is great, overclocked my 2600k to 5ghz stable on 1.44v, on my asus p67pro I could only manage 4.8ghz on the same voltage, still to work on the memory!