So it turns out that the Xbox and Amazon gift certificate are the grand prize of the TechNet Magazine TechEd Subscription Contest which ran from June 11th - June 30th.
Here is a link to the rules: https://www.kable.com/pub/tcnt/rules2.asp
I'm delighted to win, and have already faxed off my affidavit of eligibility and waver of liability. The Xbox should be winging it's way to me soon. Apparently the gift certificate is handled by Winternals and might require additional signed documents. Winternals is a bit busy right now, being purchased by Microsoft and all that, so I'm going to be extremely patient while I wait for my SUPER SWEET prizes to get to me.