So, at launch, the PS3 cost Sony about $840 to make, according to iSuppli, and they sold them for $599, resulting in a tidy loss of $200 a pop. By stripping out over 1200 parts and features like PS2 backward-compatibility, Sony has cut their costs to just $445 per PlayStation 3. Which they sell for 400 bucks, meaning they still lose about $45 a system.
That, friends, is why you didn't see a cheap PS3 for Christmas, and why you won't see one until deeper into next year at the earliest, even as the Xbox 360 outsold it 3-to-1 on Black Friday. [BusinessWeek via PlayStation Forums via PS3Fanboy]