I have installed Beta 2 of Vista on a spare machine here in order to test its suitability for imaging. I will report back after I have had chance to try it on real work.
Initial impressions are that the new interface looks nice but drains speed from the machine (A Pentium 4 2.53Ghz with 1.5GB Ram), It just may be that new high spec machines that come with Vista installed will be ok but there is no need to upgrade existing hardware to the new operating system.