This link is for Windows 7 64-bit & Windows Vista 64-bit . . .

http://www.nvidia.com/object/win7-winvista-64bit-295.51-beta-driver.html

EDIT: 295.51, not 31, my bad.

How much improvement forSkyrim?

Skyrim isn't mentioned in the release notes, so the only benefits it would receive are probably just benefits that any game might receive from general driver improvements.

There are NO performances increases with this new driver for any games. All this release does is add some SLi and 3D Vision profiles, along with a few bug fixes and an updated version of Physx. It's giving people on their forums problems with some games, but no mention of Skyrim.