I don't if they'll ship 4.1m a month but do the math:
~700k in the USA...800k in the Americas...in Mar/Apr/May/Jun
That could easily be ~1.5m to 2m in the Americas in Nov and 3m-4.5m in Dec just in the Americas. If Oct is 1m, Nov could be 2-2.5m and Dec could theoretically be 4m-5m.
DS shipped over 11m in a quarter. Wii did 6.96m in Oct-Dec 07'.
No reason to expect Wii to ship under 9m in Oct-Dec 08' and it wouldn't be hard to reach 11-12m shipped if they had them.
..thats close to 4m/month three months. The issue is alot of it might be stockpiled.
I suspect there will be a quarter where Wii does maybe 14-18m shipped, especially if the motion plus tech is well-utilized in holiday games or if Wii has a price drop. Oct-Dec 2009 probably is the most likely quarter for the peak.
Wii still has at least five major games in Japan (Animal Crossing, Wii Music, Monster Hunter, Wii Sports Resort, Pikmin) by my count so I can see DS & Wii being the opposite in peaks - early Japan peak for DS, late west peak for DS, early west peak for Wii, late Japan peak for Wii.
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