I really don't see the point in achievements. They don't give me any incentive whatsoever to either keep playing a game, replaying a game, or doing 'good' in a game. Nor do they make me search for all kinds of trivial things for little more reason than a tiny text message if I don't feel like it. I honestly think it's the most useless invention to ever come out of the industry. I don't need them to 'track' my progress in games, or what else they're for, my memory is good enough for that. I'd rather take a full list of stats on everything, or something.
That said, I don't care. Not in the slightest, because it doesn't hurt me either way.
I don't care if they stay, I don't care if they go. I don't care if Nintendo doesn't include such a system ever, I don't care if they actually do.