The N64 controller was a horrible monstrosity. Surely no one can debate that? It assumed you had three hands to hold it with. The introduction of the analog stick was the only thing that controller did right.
The DS? The touchscreen. Outside of a few games where drawing was fun, it's mostly made a hindrance. Even something as simple as navigating menus is usually a bigger pain than it needs to be because you're often forced to pull out the stylus and use it. The microphone also proved to be little more than a gimmick when it came games... the few that it was used in at all.
Do I really need to explain the 3DS? It's in 3D, which has got to be the most worthless gimmick of them all. It's useless in films and it's useless in video games. At best it adds nothing. At worse it makes your eyes bleed. No one can complain though, because no one owns it... It's too expensive.
What Nintendo has done is jumped on the tablet bandwagon. It's a gimmick market, and Nintendo likes gimmicks. The idea has some merit when paired with the TV, but it won't be utilized enough or prominently enough to justify basing an entire system around it... especially at the expense of having a
real controller. Why make customers pay for something that's not needed? It's stupid. It's just Nintendo doing what they always do: being different just for the sake of being different.