It says here that it's going to revolutionise the controller, not so much the machine. The controller looks like a white TV-remote. Gyroscopes inside will detect any movements you make. Read this excerpt to understand.....
"The key to Nintendo's new game interface lies inside the controller. Instead of using a joystick to control the game, the primary control is the controller itself. The controller contains solid-state accelerometers and gyroscopes that let it sense:
Tilting and rotation up and down
Tilting and rotation left and right
Rotation along the main axis (as with a screwdriver)
Acceleration up and down
Acceleration left and right
Acceleration toward the screen and away."(Read On)