Yesterday, Nintendo released a new Nintendo Direct, outlining the features of their brand new system, the Wii U, in preparation for E3. During which, a small teaser was shown, featuring a new Mario platformer, which may be a revamped form of the New Super Mario Bros. Mii demo show at last year's E3. While the teaser does not show very much, the game does seem to feature online communication through a function of the Wii U called Miiverse.
As well, the style of the new game seems to take advantage of the HD quality of the Wii U. Although, some people believe that this style may have been inspired by Super Mario World. Another screen shown of the game shows people using the new chat system, and what they are saying seems to imply various different features of the new game, although no information on this is out at this time.
Check out the full video here to learn all about Wii U and it's new features. The teaser for the new Mario game can be seen around the 22 min. mark.