At last year’s E3 gaming conference, Sony showed off a prototype motion-control wand for the PS3 that looked and acted a lot like the Wiimote for the Nintendo Wii. Yesterday, Sony unveiled the finished product, and it now has a name: the Sony PlayStation Move.

Sony made the announcement at the Game Developers Conference in San Francisco this week. The Move system has several different parts, much like the Wii system. The PlayStation Eye, a body-tracking camera that has been used for years in other PlayStation games, sits on the TV. The Move, the wand with a colored ball on top, tracks the main movements, and the unimaginatively named “Move sub-controller” uses a directional pad or joystick and additional buttons to control other aspects of the game, such as forward and side-to-side movement.

While initial reports from journalists who got to use Move indicate it isn’t much more accurate than the latest upgrade for the Wiimote, Wii Motion Plus, the design is much less cluttered with the buttons clustered at the top of the Move controller.

Sony finally explained why they have a large colored ball on top of the controller, too. The camera can track the movement of the ball, but it can also track the relative size of the ball from the perspective of the camera. This means the ball makes it possible for the system to track forward and backward motion more accurately than other motion control systems. The ball changes color to make the controller a different color than anything in the background, which is easier for the camera to track. This means the controller will be a different color depending on the room users play in, the ambient lighting and even what clothes users wear.

Sony debuted several games with the Move system. They include first-person shooter SOCOM 4; a compilation of sports games similar to the basic game package for the Wii; a sword-fighting game; and a game that superimposes objects over an image of the player, much like the original Eye Toy games.

Sony says that more than 20 titles for the Move will be ready for release when the entire system goes on sale sometime this fall. In addition to internal game design studios, Sony has 36 third-party developers signed up to create games for the PlayStation Move.

The Move system will be sold in several different packages. Consumers can buy a stand-alone Move controller if they already own the PlayStation Eye camera; a package that includes the Eye camera, Move controller and a game; or a complete console package that includes the camera, controller and a PS3 console.

Sony only gave price details for the controller and camera option, which will cost $99.

A further complication is that certain games, such as sword-fighting title and some sports, require two Move controllers, not one Move and one sub-controller. That means users will have to buy extra Move controllers to play some games, especially if they are multiplayer games.