I would assume it updates quicker than five days, Mstenger404. I added my serial on the night before launch, and at the time I was told by the nameplate page that I would be "Using" it when I played Reach. Unfortunately, I do not have the nameplate, and if I go and look at the nameplate page now, I am instead being told to reenter my serial. Then, when I do reenter my serial, the page tells me that my serial has already been used.