It's not just about game footage or whatever. That metric of marketing for video games is so 1990s ... it's outdated. We have the internet now, you can find loads of game footage/trailers within seconds, that doesn't make a marketing campaign good anymore.
It's about the image you create for your console/products.
The Japanese ad while simple, is refined and clean looking with an attractive spokesperson playing the game who's an adult. If Apple had a game division, this would be the type of game commercials they would make, just with an American celebrity in a New York City penthouse instead.
The American ads? The slogan may as well be "Wii U -- The Game Console For Your Kid Brother".
Compare and contrast again the NSMBU ads from last year --
http://www.youtube.com/watch?v=rWyPqlb_pYo (Japan)
http://www.youtube.com/watch?v=RBlBe06Xm0c (North America)
Again the focus of the North American spot is "it's fun for teh kids" (albiet it does show the little kid's parents playing with him for a few seconds). But overall the message sent there is it's a product for kids, right down the "annoyed big sister who wants to watch TV, makes her kid brother play Mario on controller".
Japanese and European commercials for Nintendo rarely actually have any kids in them period, whereas NOA ... I think they took a lot of heat from the Japanese division over low 3DS and Wii U sales, and have decided to simply market to the lowest common denominator -- kids. They've just pretty much decided to stop marketing to anyone else.
NOA themselves helps create and maintain the "kiddie" image for Nintendo by marketing like this.
