This game brought me back to the Wii after playing my 360 for about 6 months straight.
Really cool game mechanics and one of the only 3rd person shooters on the Wii. The only one that has the Gears of war style cover mechanic.
The weapons are all great and the Wii remote pointer makes it easy to gun people down, especially when using the sniper rifle. Throwing grenades using the aim mode can be a little awkard but just give the nunchuk a flick while aiming and it'll go in the right direction.
Graphics are a little dated but it's far from ugly and taking the enemies out by shooting their oxygen tanks and watching their bodies thrown ragdoll style at a wall is always satisfying. The level design is really great too.
Loads of action and great controls make this a great, fun game. Every proper Gamer on the Wii should buy and play.