I personally find it much quicker than xp, and unlike XP it doesnt slow down over a few months like xp does.
That's true huh. XP my system would slow down visibly after a few months of installing programs and begin taking a minute to reboot instead of seconds like after a fresh install. But with Vista 64 its different, a few months and tons of programs later after installing it still runs like I just installed it yesterday, mine boots up in like 20 seconds and I've got a lot of programs/games on it.