From all the reading I've done, there is no GK110 for gaming coming out in 2012, only GK110 for industrial compute applications. You might see a minor speed refresh of GK104 but GK110-esque card likely won't be out until Q1 2013, or extremely slim chance of nov/december of this year at massively high price.
My advice if you don't want to wait 6 months+? Get three 4GB GTX670s that have reference GTX680 HSF:
The Zotac 4GB GTX670 has a gtx680 pcb, gtx680 hsf, gtx680 power components - with one smx disabled and slower clockrate than gtx680. Some room for OCing with the 680 HSF/power likely. Going for the 680 4gb not worth it when you are getting 3 cards as it incurs an extra $300 cost without $300 worth of fps to match it.
And its only 449 and has 4gb vram, so get three in SLI and it will destroy a GTX690 (one less gpu and only 2gb vram per GPU). Even two in SLI would beat a 690 in applications such as triple monitor surround and skyrim high texture pack with it's extra VRAM.