Is how many of those 25m are replacements for failed units? I have had 3 failied Xbox360's. 1 of them replaced by Microsoft, but 2 of them swapped by the retailer, as they failed very early on in their life. When the retailer replaced them, they went through the till as a new sale.

I bet there are only about 20m ACTIVE Xbox360's out there....

Probably very few are replacement units. The retailer is unlikely to sit on them or throw them in the bin, likely they go straight back to MS. I would guess that not even MS can spin the figures so that returned units are "sold" units.

I would be very easy for Microsoft to ignore failed units. If retailers sell 4 units, 1 of which is a replacement, it's pretty easy for Microsoft to just NOT bother marking the numbers back down.

I wasn't suggesting that the retailers were sitting on them, they surely send them back to Microsoft, but knowing how dishonest Microsoft are, I suspect they don't bother marking the sold numbers back, based on failures.

I forgot to post something about how well the PS3 hasnt sold... bugger