Radeon HD 4790 reported being in the works
 

According to info floating around the interweb, AMD is going to let its partners release a new Radeon HD 4700 series cards that's not powered by a 40nm GPU. The Radeon HD 4790 is supposed to feature a 55nm RV790 GPU (the same one used for the HD 4890), and thus offer 800 Stream Processors, a 256-bit memory interface and 512MB of GDDR5 memory, DirectX 10.1 and CrossFire support, and probably quite a bit of overclocking potential too.

http://www.tcmagazine.com/comments.php?id=27202&catid=2