During GDC last night, Nintendo took the opportunity during their keynote to announce Super Mario (yup, that's the full title) for Nintendo 3DS. It's being developed by the Super Mario Galaxy-team, which in itself makes the game sound promising right from the start. According to Nintendo themselves it will be the same three dimensional revolution that Super Mario 64 was once upon a time, but they would of course say that.
Note the tail on the "O" in the picture below. Tanooki?