Amazon posts warnings on the Xbox 360 pre-order pages that orders might not be filled on release day in Europe (December 2nd). Additionally Amazon has stopped to take pre-orders of Microsoft Xbox 360 bundles in the United States.
See the Xbox 360 order page on Amazon UK and the order page on Amazon Germany for the warning:
"We have been informed that the Xbox 360 will be in short supply on the day of release, and, unfortunately, this means we can't guarantee that pre-orders will be delivered by day of release. We are working with our suppliers to ensure that we fulfill all orders as soon as possible, and will ship the consoles as soon as we receive them. "
This supports the statements from a recent BBC news interview with Microsoft's J. Allard, quote: "We are going to have some disappointment with retailers and consumers".
You might have to revise your budget, if you want to have a Xbox 360 for the holidays. If Microsoft cannot satisfy the demand for the Xbox 360 consoles, they will only sell for ridiculous high prices on eBay.
As Microsoft is the one who informs the retailers of potential short supply of the Xbox 360, it all can just be a smart marketing scam too. Who knows, I tend to believe that MS is really not able to meet the demand for the Xbox 360.
Currently mostly Xbox 360 email account offers are found on eBay, when searching for Xbox 360. Honestly I do not understand anybody who pays for an email address containing the string Xbox 360.