a quick check of Nvidia's 266.7x beta drivers, VR-Zone found two quite interesting entries inside the .inf file. The Nvidia Geforce GTX 590 and the Geforce GTX 550 Ti are currently listed in the driver but we are sure that more details will surface pretty soon.
We already wrote a lot about the GTX 590, Nvidia's next dual-GPU graphics card. It will be based on two GF110 GPUs and will feature 3GB of GDDR5 memory. The new GTX 550 Ti will apparently look a lot like the GTX 560 Ti and might even use the same PCB. According to the info, it is based on the GF116-400 GPU and features 1GB of GDDR5 memory.
You can check out more here