I tried installing Vista last year on my late 2008 MacBook, but quickly removed it since multi-touch wasn't supported. Has the situation changed at all for Windows 7?
Well Apple have released a patch for Multi-touch trackpads in XP/Vista with bootcamp.
If you're using VMware Fusion to run Windows 7 like I do, then it's already supported :)
Since Windows 7 is not officially supported by Bootcamp yet and since Apple has not released any new drivers since 2.1 I would assume the answer is no.
However Windows 7 does have standard support for Multi-Touch devices, so there is a pretty could change it will support it. My experience with the multi touch Dell however was that the correct drivers first had to be loaded before it worked.
Also, since Windows 7 is similar to Vista because of the codebase you can install it on a Mac happily, using the existing Vista drivers.