I think that Nintendo's version of achievements is going to be something more simple than the other systems. I expect something like getting one gold, silver, and bronze star or medal per game. The bronze will be like playing halfway, the silver for beating the game, and the gold for completing it 100%.
Or at least, that is what I was expecting, but if that article has any truth, there may be a bit more to it. In any case, it's definitely going to be different, since that's the way Nintendo operates.