April 27 In The U.S.
Via Nintendo - Sorry, Don't Know How To Get It Into Quotes So I Will Make It red. Here Is Their Official Press release
NINTENDO SPEEDS INTO SPRING WITH MARIO KART WII
Hotly Anticipated Racing Game Includes Innovative Wii Wheel
REDMOND, Wash., March 12, 2008 - This year, the typical signs of spring will be accompanied by the sweet sound of revving engines and the sight of lightning-fast shells whizzing around every corner. Mario Kart® Wii is zooming toward its launch in the United States on April 27. The game comes with the intuitive Wii Wheel™, which makes it easy for novices to compete against veterans, so no one is left in the dust. And with a broadband hookup to Nintendo® Wi-Fi Connection, players can compete with up to 11 other drivers from around the world for racing dominance.
"Mario Kart Wii transforms one of our most popular franchises into a race that every member of the family can join," said Cammie Dunaway, Nintendo of America's executive vice president of Sales & Marketing. "Driving with the Wii Wheel could not be more natural, and this is one place where speeding is encouraged."
Mario Kart Wii will include 16 new courses and 16 classic courses from previous Mario Kart games. For the first time ever, players have the option of racing with either karts or motorbikes. Players can also hit the road as their personalized Mii™ caricatures in addition to the handful of classic Nintendo characters found in the game. True to the series, the game features tons of racing, plenty of power-ups and oodles of objects for players to use to slow down other drivers. And 10 battle arenas will keep players busy between trips around the circuit.
The easy-to-use Wii Wheel will also be sold as a separate accessory, giving every driver in the household a chance to get behind his or her own wheel. And if veteran Mario Kart fans are afraid of getting smoked by rookie drivers using the Wii Wheel, they can rest assured that Nintendo has them covered. Mario Kart Wii supports four different control options: Wii Remote™ with or without the Wii Wheel, Wii Remote and Nunchuk™ controller combo, Classic Controller and even the Nintendo GameCube™ controller. So there's bound to be a configuration that fits everyone's style.
Mario Kart Wii launches with a new channel added to the Wii Menu to enhance game play: The Mario Kart Wii Channel. This new channel builds on the huge online community of Wii owners and lets players compete in tournaments, check worldwide rankings, see when their friends are playing and download ghost data.
Remember that Wii features parental controls that let adults manage the content their children can access. For more information about this and other Wii features, visit Wii.com. For more information about Mario Kart Wii, visit MarioKart.com.