UPDATE 2/4/15 0.15am: Nintendo has officially announced Pokémon Rumble World during its just-finished Nintendo Direct broadcast.
Nintendo has announced Pokémon Rumble U, a downloadable game for the Wii U eShop.
It's the third in the Rumble series of spin-offs featuring animated Pokémon toys.
The game's existence was revealed in Japanese magazine CoroCoro (thanks, Serebii), scans of which have found their way online.
Zelda: Ocarina of Time 3D and Nintendogs + Cats saw healthy sales bumps in Japan last week thanks to the 3DS price cut.