With the RTM version of Windows XP SP3 out this week I decided to give it a try. My laptop is a Lenovo T60P Widescreen with 4 GB RAM. I run both Vista and XP in classic mode so I can't really comment about Luna vs Aero.

For general windows stuff (eg. exploring folders/files etc) XP SP3 felt a little faster than Vista. Notice I said 'felt' - because as a human I can only comment on perceived performance not actual performance. However I did find one major application significantly slower on XP SP3 and that was Office 2007.

It turns out that Office 2007 runs much faster on Vista than XP. It turns I write a lot of emails. This means that Vista is my OS of choice. So after a day on XP SP3 I'm back on Vista. I'm in between beta testing at the moment (which is relatively rare at Microsoft). I was using IE8 for a while but it's still a bit rough and even with the compat mode I had to use Firefox a lot for some sites (which is painful as I find Firefox slower than IE). I'd use Safari more but it's lack of phishing filter really turns me off. At some point I'll emotionally commit to beta testing Office 14 and run a new build every few days (a nice benefit of being part of the Office division).