Vista - do I or don't I?

I just received my upgrade copy of Vista from Dell, several months after ordering my spanking new laptop. Now I'm torn - do I wait until SP1 or do I just go ahead and upgrade from XP.

This, I know, is a dilemma facing a lot of you, especially those with multiple computers to manage. My laptop's new, so I'm not too worried about the hardware keeping up (though I really want to try out ReadyBoost), and my few peripherals are pretty recent too. On the other hand, there's no compelling reason for me to upgrade - XP suits me just fine.

What to do? I reckon I may succumb to the inquisitive geek within and give it a shot, but I will of course keep you updated as to my progress.