The figures for hardware don't really matter. Most quarters system sales are going to be split like this in the current market:
Americas EMEAA Japan
Wii 40-50% 35-40% 15-20%
PS3 35-40% 40-50% 15-20%
X360 58-63% 32-35% 3-10%
PSP 20-25% 35-50% 30-40%
DS 35-40% 35-40% 20-30%
(For Wii, Nintendo has shipped 36-37m / out of roughly 77m Wiis through Sept to the Americas, 11m / 77m to Japan, and the remaining systems to EMEAA - roughly in line with my guesses above. For X360, the 1.3m X360s in Japan are 3%-4% of ltd 360 shipments, and the 24-25m X360s shipped to the Americas roughly fall in there too...same for PS3 and the others).
My point is even if Vgchartz & NPD stopped giving numbers you'd all still be able to track hw sales by following figures from earnings releases.
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