Could someone please explain to me what the dif is between VISTA OEM and VISTA FPP? I have read the licensing req for VISTA but this did not help...If you pay $319 for the FPP VISTA, what do you get that you would not get if you bought the OEM? Both versions can only be used on one cpu so why would anyone pay double the price when you can buy the OEM for $159? I know I am missing something because M$ would not sell anything for half price? Thanks for your help!!!!