i just wonder how your calculation will look like manbear?
i just made it for myself and you said japanese home console market isn't so big.
japan is like: 12.5m wii and 8.2m ps3 against 1.5m 360s atm
no clue where the sales will end but let's say next gen, nintendo would be at 10m, ps4 at 8m and 720 at 3m at the end of gen (just as example)
this would be an 15m advantage for wii/ps4.
if wii u would only sell 40m and ps4 40m in america and europe, xbox 720 would have to sell 95 million there? so xbox would have to grow a lot and wii u and playstation would have to lose a lot sales?
i have no "rest of world" numbers now but i believe playstation brand is much stronger there so i don't see xbox 720 selling more than playstaton and nintendo together. so even if they would be the same there, my calculation above (which would be very low for nintendo as example) had to come true