Not once while playing a Nintendo game have I ever thought, "Man, if only I was receiving arbitrary rewards that had no effect on my gameplay experience, I'd be having way more fun right now."
On the couple of platforms I do use that implement achievements -- namely, Steam and iOS -- they are entirely uninteresting to me. Sometimes I look at them and I think, "Oh, those are things." Sometimes it pops up that I got one and I think, "Alright."
That said, Smash Bros Brawl and Kid Icarus: Uprising feature the best implementation of achievements I've ever seen in a game. There may be some other games I haven't played that use them this way. Most achievements in Uprising actually unlock something new (it could be a new multiplayer stage or a new weapon) or reward the player with something tangible, like a weapon, collectible idol, or even just hearts (currency). Thus, the achievements list serves as a 'hints' screen for unlocking everything, and all the while you're uncovering a nice piece of concept art. So if Sakurai wants to keep using achievements, good on him. I like the way he uses them in his games. I don't have to show off my big dilist of achievements to my friends on the internet.
