Even if Nintendo stopped manufacturing the Wii today, it has already been a unprecedented success in terms of both sales and profits.
At this point, it almost doesn't matter if they changed their strategy to focus on 3DS sales and soft development.
Naturally, Nintendo will still have to maintain adequate software support until the next gen successor is announced, even if for nothing other than to keep the Wii brand relevant, but they've already reaped all the benefits from the success of the platform, regardless of sales from this point onward.
And while I still think there are untapped markets at a $149 entry price, price restructuring at this point probably won't set sales on fire again without another broad appeal hit like Wii Fit. But nothing game changing has been announced, the Vitality Sensor is MIA and was never positioned as The Next Big Thing from Nintendo anyway, so sustainment of sales and maintaining brand relevance are more or less where the Wii is at through the remainder of its life cycle.
Even if the Wii closes at 40% marketshare, Nintendo is still the market leader. I have a hard time seeing either the 360 or the PS3 closing at more than 33% by comparison.
