This is a really good thread, before I say anything else..
ok,
Wii- 18.5 million. It has sold 6 million in 4 months, and with nintendo upping production and this holiday season guaranteed to be huge, I am following a "6 million for every 4 months" idea, but giving it a little extra in sales because I expect the holiday season to be huge for nintendo. Nintendo has too many huge games coming this holiday for it to be unsuccessful. Nights 2, Mario and Sonic at the Olympics (whether you like the dea or not, the game will sell huge), Super Smash Bros. Brawl, Mario Galaxy, as well as a few other big games, all in Q4... it's just too much all at once for the Wii not to sell, it might even start selling out again.
360- 18 million. It would just barely end up not retaining it's lead. Summer will be a bit slow, but will have a huge holiday season, possibly as big/bigger than nintendo's, however the slow summer will keep it from keeping it's lead. Halo 3 will be huge, although GeoW and the few other FPS games coming soon will weaken Halo 3's selling power a bit. The high price point of the elite could hurt, but I doubt it. GTA IV will also be huge.
PS3- 8.75 million. PS3 has very few killer aps this year with the exception of maybe ratchet and clank in september. GTA IV won't help sell systems because it is coming to the cheaper 360. Holiday season will be decent, but nothing spectacular. It will have a few hits throughout the year to keep it alive, but nothing to make it sell through the roof.
DSL: 56 million- It will continue it's path of dominance, as expected. Pokemon D/P in US will give a huge boost, as well as phantom hourglass.
PSP: 28.5 million- now that the NDS has basically been chosen as "thee handheld" the PSP will see a slowing in sales. This happened with the PS2, at a certain point the PS2 just took off as the chosen winner while the others slowed down a bit. Check the sales charts and you'll see it happen with the PS2, it happens over the course of a month, instantaneously practically.
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