"In a recent interview, Mr. Miyamoto confirmed that a new Super Mario Bros. game for the Wii U system will be shown at this year's E3 Expo. This is based on the Mario experience that was demonstrated at last year's E3 Expo. We'll have more to announce about our plans for the E3 Expo at a later date."
So it was kinda obvious last year that they wouldn't produce new levels and show this off and then not make it a game. I wish, though, that the "new Mario game" would come with a completely different art style. Little bummed out, that it's "just" another one of the New Super Mario bros games ..