I used to run Vista 32 a bit back and it made me sick.. hated it and went back to XP. Recently built a new rig and put Vista 64, HUUUUGE difference.. I find it very likable now.. it's fast, looks good (reminds me a bit of linux). still have little nags about it but nothing serious. My system gets a 5.9 in it.
Personally I think M$ should look in to releasing specific OS versions to suit the users main task.. e.g. gamers get a stripped version of vista with streamlined programs made specifically for gaming etc.. they did try to do something similar but basic, enterprise and ultimate or all based around the system you have rather than the tasks you use it for..