Brain Training is really Studying: The Game. Wii Fit is Standing Straight: The Game. Wii Music is Noodling: The Game. There's nothing wrong with that approach. Those games are popular, and they've made Nintendo gobs of money. Nintendo didn't always make those kind of games. Shigeru Miyamoto explains his change in approach:
I have a much greater degree of freedom. In the past, I would develop a game and then finish it and the next question is always: What is the next game we would create? In recent years, I've really found that with this idea of applying the structure of video games in a variety of ways, I've found anything can be a video game, and I've found a greater degree creative freedom in what I want to do next and explore.
That's good Miyamoto has grown as a game creator. And sure, anything can be a game, but not anything can be a good game. Nintendo game guru expands creative limits [SF Gate]