RE4- Wii Edition is the 3rd version of the popular game, originally released for the Gamecube. The Wii Edition might be called the definitive version of the game, since it includes the better graphics and progressive-scan of the Gamecube edition and the extras and widescreen support of the PS2 remake. This version also adds a new set of Wii-specific controls which make full use of the remote.
The new controls are an excellent addition to the game, and make it worth purchasing again. This version adds an onscreen reticle that follows where you point the Wii Remote. The controls are amazingly accurate, and really show the capabilities of the Wii. In my opinion, it makes the game a bit easier, since aiming is a bit easier, but it is very viscerally satisfying to physically aim at your opponent.
The one caveat to recommending this game is that it is very violent. Heads explode and blood spurts all through the game. If you aren't worried about this, though, it's a great game, and well worth purchasing even if you already have it on the GC or PS2.