I just upgraded to Vista SP1 and I saw a huge difference in speed and overall performance of Vista. I noticed performance differences in the final areas:

• Aero - SP1 allows me to run Aero now without Super Lag. Before Aero made my comp so unusable cause of lag. I know 512MB is not alot but after SP1 I can finally use it
• File Operations - Coping and Zip Extraction is alot faster in SP1.
• Overall Performance - I noticed Garry’s Mod ran a tad bit faster with SP1 then with RTM and just overall my experience with Vista went from hating it to actually liking it

I been testing SP1 Sense the Last RC and recommend all Vista users to upgrade now