Vista OEM activation on new computer

I've bought an OEM copy of Vista Home Premium (Full). Some are saying that once I install it in my computer, which I just built about 5 months ago, it will be locked into that motherboard, and if I build a new computer, with a new motherboard, Microsoft will prohibit me from activating Vista again, even though the motherboard and CPU may be the only new parts in that computer.

I know it's early in the Vista life span, and that very few may have run up against this problem, but has anyone actually had this happen? Does Microsoft specifically say somewhere that this will be the case?

I've got an OEM copy of XP, that I've installed into two more computers after the original Gateway that it came on. In all cases, even when reinstalling with all new parts, the activation has been seamless.