I'm pretty sure you can. Only one can be in use at a time,however,and there are other restrictions. Details available,just can't find the link right now. So if ,say, you have a home PC and a laptop, no problem,skin'em both.
That's awesome! Following that line, I can install WB in Vista and XP, same machine, while I'm deciding wich one I'll keep.
Forgot to say, thanks goes to Wizard1956