Can I install it side by side with 32? Will there be a nice little boot loader like with Vista/XP duel booting?
yep, though they will both show up as "Windows XP" IIRC. youll have to edit the boot file to change the names if you want to make it more obvious.
Anything I should look out for?
Ta.
Some of the more obscure hardware isnt supported very well. Modern stuff youll have zero issues with, but some older hardware just doesnt have the drivers.
Other than that its pretty good, it "feels" quicker than normal XP, and ive found im gaining slight advantages in some games. Crysis Demo for instance im getting ~5fps more on the XP64 boot than the XP Home boot. I think it may be down to the fact XP64 is handling the complex maths a lot quicker without having to break the numbers apart. Oh, and my XP Home and Vista boots are about to go byebye anyhow, ive just got another 2Gb in the post this morning, and I want to be able to use it!