During a Nintendo retailers conference in Japan yesterday, Nintendo announced a new Pokémon game for the Wii. PokéPark Wii Pikachu's Great Adventure (ポケパークWii ピカチュウの大冒険) is scheduled for release in Japan on December 5th, 2009. More details will be announced closer to the release of the game.
PokéPark Wii Pikachu's Great Adventure is game based on the PokéPark amusement facility. Players have to go through and clear various attractions where they will meet a variety of Pokémon. Pokémon can use their abilities to make the attractions even simpler such as Water Pokémon in the Marine Slide and Flying Pokémon in the Sky Race.
Source:
http://www.amazon.co.jp/