It appears that even though sales of the new Microsoft Xbox 360 are through the roof Microsoft may still be losing money. The premium edition Xbox retails for 399.99 but cost 525 to produce.
This loss may have been avoided if Microsoft had raised the initial release price of the Xbox because they were selling on EBay between 690.00 and 1800.00.
This loss may be being taken up by more than just Microsoft; some of the hardware manufacturers may also be taking a hit. The most expensive part of the Xbox is the chips inside for a total of around $340. source