there are so many rumor out there. many expect the new series will come out in march/april time line though we don't know which card will come out first. earlier most people expecting the 600 series flagship around march/april but the latest leaked roadmap showing nvidia high end card will only come out at the end of 2012 or early 2013. you should check this tread if you want to know more:

http://www.tomshardware.com/forum/331651-33-7xxx-series-rumors-technical-data
 

Fci-dk

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Dec 2, 2011
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yeah,, cant find out anything about a release date too
, but my 4870x2 cant keep it up anymore,, so guess the upgrade will be a 590 then, and hope im not gonna smash my head into a wall in jan, or feb ;)
 

Not so fast.... this quote is in regards to the AMD 7950 and 7970 cards:

"Both products are expected to be released during CES 2012 and will occupy the $349-449 price bracket, while the dual-GPU version of Tahiti, the HD 7990, will debut in March 2012 and the target price is the same as the original price of its predecessor - $699 (520 EUR)."
http://www.guru3d.com/news/amd-radeon-hd-7950-and-hd-7970-gpus-details/