No, it doesn't. I am not using Glass and the OS in general is still more responsive and faster to boot than XP.
Now here's the thing I've been wondering, has anyone here got a Vista fully loaded with a crapload of crap installed/laying around?
I always found XP boots fast as hell within the first month of installation, but after awhile it just keeps bogging down over time, Vista got a routine built-in to keep things running smoothly in that area or something?