[quote name='topdolla69']I just bought an xbox360 and I have received no such offer[/quote]
It depends. Was it new or refurbished? It probably won't show up on a refurbished 360, but if it's new, then what you do is choose to keep silver when they ask you what kind of subscription you want. They'll ask you twice, and you say you still want it. Then they'll offer you the month for free.