Pieter, over at LapTopVideo2Go, has managed to extricate Forceware 85.05 from the latest Vista beta.

He also has Forceware 86.70 for Vista posted on his site.

According to Pieter;
"Vista drivers come with 2 INFS, one for Mobile GPU's (nv_DM.inf) and one for desktop GPU's (nv_LH.inf) Vista supports the latest GPU's but if you have an older GPU a modded INF will be needed (or anything but a Dell Laptop) Grab the appropriate INF from above and replace the original, it may pay to remove the other INF from the driver dir. Now goto System Properties and then display, now use driver update to install the driver, by pointing the wizard to the driver direcotry with modded INF and Vista files.

Remember Vista LDDM drivers are very small and DON'T have control panels so you can't can't change any settings. Also you MUST have a pixel shader capable GPU for Aero Glass effect to work.
I have enanbled this in the INF should your GPU be capable of it but Vista's machine check decides not to enable it."