Miyamoto has confirmed it in an interview
Miyamoto was interviewed by a Spanish newspaper and he revealed that the new Mario will be shown in the E3.
According to reports from the Spanish newspaper 'El Mundo', Miyamoto has revealed Nintendo will show a new Super Mario game at the E3 this June. This new Super Mario game will be launched, obviously, for the Wii U. The new Mario game will combine action on the TV with some elements from the tablet screen.
Miyamoto also said that he is working on some small, but important projects for the Wii U and he's very focussed on Pikmin 3 and Luigi's Mansion 2 (this one for Nintendo 3DS). He also said that he wants to make something using the Wii Music idea.
Miyamoto is getting older and he's already thinking in his retirement from Nintendo, so he's training their young crew at Nintendo to keep innovating in the future.
NEWS SOURCE #1: http://www.videogamer.com/news/nintendo_to_show_a_new_mario_game_for_wii_u_at_e3.html
NEWS SOURCE #2: http://www.elmundo.es/elmundo/2012/04/16/navegante/1334559905.html
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