Nintendo confirmed today the US release dates of its WiiWare and WiiFit. Wii Fit, which will go on sale on May 19, comes with a device called Wii Balance Board.

Shaped like a household body scale with a white top and grey bottom, Wii Balance Board connects wireless to Nintendo’s Wii and it contains pressures sensors used to control the virtual movements. Also, the sensors are used to measure the user's center of mass and body mass index.

Wii Fitness includes more than 40 types of training activities which falls into four fitness categories: Aerobic Exercise: 10-minute exercises that are designed to get the heart pumping, Muscle Conditioning: Controlled motions using arms, legs and other body parts, Yoga Poses: Classic poses that focus on balance and stretching and Balance Games: Fun activities, such as ski jumping and heading soccer balls, which challenge the player’s overall body balance.

The players will be able to compare their results and progress on the new channel on the Wii menu. Two key measures are evaluated: Body Mass Index (BMI), a weight evaluation based on a ratio of weight to height and Wii Fitness Age, which is measured by factoring the user’s BMI reading, testing the user’s center of gravity and conducting quick balance tests.

In Japan, Wii Fit has sold more than 1.4 million units since its December 1 launch. According to Gamasutra, officials from Nintendo of Europe have confirmed local release dates for Wii Fit in April.

Also, Nintendo announced that its WiiWare will be opened on May 12. WiiWare is a a game-creation service that will allow developers large and small to create new downloadable video game content for sale by Nintendo through the Wii Shop Channel. Players will be able to purchase and download WiiWare games directly from the Wii Shop Channel in exchange for Wii Points. Wii Ware was announced in June 2007 by Nintendo, but Nintendo wasn’t very specific about the pricing scheme.

Early WiiWare games will come from celebrated developers like Square Enix, which is creating FINAL FANTASY CRYSTAL CHRONICLES: My Life as a King, a simulation game for all ages. In Europe, WiiWare will be available in April.