I think that Wii can still sell very well in those markets.
Wii is still a very ease to use console, has a great library of games and if Nintendo pushes Wii with two controllers/nunchuks, compiles 2 games in a single package, pushes Wii VC and Wii Ware games, for example, i don`t see a reason for countries with lower incomes or in some cases countries who are seeing an increase in income - like Brazil -, wouldn`t support Wii.
It will depend on how Wii will be sold and marketed.