Good co-op campaign, graphics and humor. Boring gameplay, no story and repetitive missions.
Graphics and sound: The graphics and sound are ok. They are not spetacular, but work very well. The game looks like a well made cartoon. Definitely, they are not the reason for a 6.5.
Story: i believe it is poor. Few dialogues, not intriguing nor interesting. Undoubtly, it is the game weekest point.
Gameplay: repetitive and boring. Althought people may affirm that it contains some RPG elements, i think it is no more than the character evolution system. No important decisions are taken by the main character. The shooting system is similar to call of duty execept for the health bar and variable weapon damage that reminds of fallout 3. To sum up, it looks like fallout 3, but has no story but a cooperative multiplayer. I always prefer better gameplay and story. If you want multiplayer try call of duty or bad company.
That's all folks!