No problems with Wacom, they have nice 64 bit drivers. One of the first companies to offer them in fact.

About content/projects, i use a separate HDD just for that anyways, so its just a matter of hooking it up setting paths and stuff.

And as for duplicate installs, I dont think you really need to do that. Even if you need the 32 and 64 bit versions of the same app, it's easier to just install them both on xp64. The only 32 apps that have trouble running under xp64 are those use some kind of driver for whatever reason. eg A popular such use is for licensing and if that isn't 64 bit compatible, you will have problems. That's pretty much the only reason to keep xp32 around, everything else you should install to xp64.