I don't recall seeing an active thread regarding the upcoming Nvidia Kepler cards so thought I would make one to share this bit of information.
According to this link, the "680" is supposed to be released april, the "670" in may, and the "660" in june. If this is true.. that's a long time to be waiting...
Also found this link saying that Nvidia may push the release date for the 680 into a late February launch, which is much better than waiting until April..
Take this information with a grain of salt as I don't know how reputable/reliable these sites are with their information and most of the stuff on Kepler at this point is pretty speculative.