I tried vista ultimate and I wasn't impressed, the font doesn't scale properly when you increase the dpi to make fonts bigger on very large moniters, it uses ALOT of memory (500+ mb compared to xp's 100mb foot print), DRM is built into the os and I am not a fan of drm, did I mention drm? oh noes you can't copy that mp3!.., the drivers are in a rather beta'ish state right now, vista really doesn't offer anything (new) other then some security measures that helps lockdown the average joes computer, the price 500? wtf.
now the good
the aereo interface IS very nice looking, for using an boatload of ram it still runs games fairly quickly (on average about 10 fps slower then xp, its alot more secure out of the box then xp is, better networking support then xp.