According to the latest Game Informer, a Wii Zelda game has already been in development for a year.

That's not The Legend of Zelda: Twilight Princess, which was recently released along with Nintendo's console. Twilight Princess was originally a GameCube title that was eventually released on both consoles. Rather, a completely Wii-specific Zelda game is also in the works.

Judging by the long wait for Twilight Princess, it seems unlikely that the newer title would see the light of day in 2007, but that possibility is not completely out of the question.

The same story also reveals that the DS's The Legend of Zelda: Phantom Hourglass has been delayed until October of 2007.

Source: Computer and Video Games