...is cute for 5-10 minutes but grows quickly boring.
It's straightforward: you use a bounding box to pan around the screen with your reticle which you aim with the Wiimote pointer. You can also use the d-pad to move the screen. You basically have a hand-drawn picture which is the game field and, as the title suggests, you shoot a plethora of cartoon chickens with B and reload with A. Reloading is manual so you cannot simply mash B endlessly.
As for the chickens, they'll occasionally hurl eggs at you, which you can shoot out of the air, but I don't think there's any downside to being hit other than having a small section of the overall screen covered with yolk for a few seconds.
As for the storyline, I remember hearing something about an invasion of alien chickens, but I don't see this as being at all represented in the game. These colorful cartoon birds will be found doing a range of things from listening to music to knitting, but the majority will be flying past the screen as you attempt to gun them down. The aiming works relatively well, but the real issue is that each level is timed and there's no real purpose to the game other than to score points and move onto the next level. You can shoot chickens carrying briefcases labeled with machine or shotguns and get a different weapon, but the same premise remains. The other issue is that, other than 1-2 level-specific chickens, all of the chickens which show up are the same. The chickens flying by, the old lady chicken knitting and the chick listening to music are all the exact same sprites with the exact same animation on each level. Even Wii Play's shooting game was better conceived than this.
It's a cute diversion, but I couldn't recommend anyone pay full price for this game (I rented it through Gamefly).