Why do the same people who assume that the PS3 and XBox 360 are just one major game release and one price reduction away from a massive sales increase, believe that the Wii couldn't maintain its sales even with several big game releases and a price cut?
After 30 months on the market, the Wii is (potentially) the longest running console that has never seen a price reduction. If Nintendo reduced the price of the Wii by $50 and/or bundled an additional controller (Wiimote + Nunchuck), created and promoted a greatest hits library (games for $20), released an smaller or colored system, started bundling other/more games, and/or released some big games (new Zelda for example) it is likely that Nintendo would at least maintain their sales level for the next 12 to 24 months ...