Just because you ordered expedited shipping on that Apple TV doesn't necessarily mean you're going to get it on time. Apparently, several customers have gotten emails from Apple indicating a 2-3 week delay and offering a refund for the shipping charge.
According to Apple Insider:
"Our records indicate that when you placed your order you paid for upgraded shipping," Apple wrote in the emails. "Due to a delay, we may have not been able to meet our delivery commitment."
It's not exactly a white iPhone 4 situation, but it's another in a series of delayed product launches from Cupertino. Although in this case, that probably just means demand has exceeded expectations. [Apple Insider]