All things being Vista today, NVIDIA is also joining the party with new 32-bit and 64-bit Windows Vista drivers. ForceWare version 100.54 includes the following support in Vista:
DirectX 9 support for GeForce 6/7/8 series GPUs
DirectX 10 support for GeForce 8800 GPUs
OpenGL support for GeForce 6/7/8 series GPUs
DirectX 9 and OpenGL NVIDIA SLI support for GeForce 8800 GPUs will be available on January 31, 2007 in a new driver from NVIDIA
DirectX 9 and OpenGL NVIDIA SLI support for GeForce 6 and 7 series GPUs and DirectX 10 NVIDIA SLI support for GeForce 8800 GPUs will be available in a future driver
For those waiting for SLI support in Vista with DX9 games that driver will be available tomorrow. You can discuss this new driver here.