One downside I am noticing is that the sidebar does not want to refresh all the time. I have my Outlook Tasks and Calendar on it, and when I update to a new task or make a change, it does not update right away. Maybe there'* some registry tweaks to this?
I also turned UAC off. That'* just plain annoying. I'm sure it'* great for the click-happy folk, but I don't need it.
In all actuality, XP SP2 works fine for me, and I can always put a nice skin over it to make it look like Vista ... or even OS/X
. I got it for free though, and I have a ton of storage space, so I'll be playing with this for a while.