Some information about the upcoming NVIDIA G92 GPU was on X-bit Labs forum. I don't know how accurate this information is so take it with a grain of salt.
According to the info the G92 will be made on a 65nm processor and will be twice as fast than the GeForce 8800 Ultra in real world games and applications.
GeForce 9800 GTX (G92) specifications:
- 65nm process technology at TSMC.
- Over one billion transistors.
- Second Generation Unified Shader Architecture.
- Double precision support (FP64).
- GPGPU native.
- Over one TeraFLOPS of shader processing power.
- MADD+ADD configuration for the shader units (2+1 FLOPS=3 FLOPS per ALU)
- Fully Scalar design.
- 512-bit memory interface.
- 1024MB GDDR4 graphics memory.
- DirectX 10.1 support.
- OpenGL 3.0 Support.
- eDRAM die for "FREE 4xAA".
- built in Audio Chip.
- built in tessellation unit (in the graphics core"
- Improved AA and AF quality levels
The expected retail date of the G92 is November 2007. There will be two products at launch: the GeForce 9800 GTX which will sell for $549-$649 and the GeForce 9800 GTS which will sell for $399-$449.