TWRoO on 13 August 2008
The Source is correct... Ifthe ratio in USA is 7.5 for the X360 it will not be the same worldwide because is is almost assuredly lower in other regions.
In fact we know it is lower in Japan... just check VGCs Japan weekly, its 4.64 in Japan.... Of course Japan having such a small portion of X360s sales means it won't affect the WW total much, but "others" ratio will also be lower than 7.5, my guess would be around 6-6.5, but I just pulled that out of mid-air.
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You're ratio of 1st:3rd party sales is correct though.... I am pretty sure MS only takes about 10% of sales... Sony is probbably between 20% and 30%
Edit... Hmmm. The Source clearly thinks MS and Sony 1st:3rd ratios are much more even than I did... I'd trust him over me if I were you 
