The New Nvidia 101.70 Windows Vista leaked drivers are out and we saw them on Guru3D's download page. The drivers in their original form are intended for the upcoming GeForce 8600 graphics cards. Guru3D included the modified .inf file. The driver is marked as "Again ... highly beta !".

 
Apparently there is a new control panel with these drivers which is a good thing, however the bad thing is that the drivers have a lot of stability problems. There are some reports that by installing these drivers fan control gets disabled in nTune.

 
It seems that 32 bit drivers don't crash in games and it only happens in some isolated cases. The most common crash on 64 bit is the following: after about 20 minutes of playing a game you get a nvlddmkm.sys error.

One other interesting thing is that apparently in some cases after you install the beta, Windows Update should update them to 101.70 WHQL drivers, but again, this is not yet confirmed.

 
It is up to you, should you try them out or not ? You might even be one of those lucky guys who don't have any problems with the new drivers.
You can get them from Guru3D here.