This game aims to give you a workout and will ship with a device called the "Wii Balance Board". This board is used to track your movements during various fitness and sport activities in the game and will also measure your weight.
According to Nintendo Wii Fit will feature 40 games, including hula hooping, yoga, pushups, heading soccer balls, ski jumping, stepping, fitness and aerobics exercises and much more.
It looks like this will be another bestseller for Nintendo. Unfortunately the company didn't announce a launch date yet.