Don't let the cartoony graphics fool you, Team Fortress 2 is no childs play. With so many futuristic war shooters, Team Fortress 2 is a breath of fresh air with its innocently seeming pixar-like but violent graphics and true team oriented gameplay.
Team Fortress breaks up the game into 9 distinct classes. Each class has their own unique weapon and their own unique role. There is bound to be a role for every type of First Person Shooter player. If a player enjoys grenades and destruction, the demoman is the guy for him. If the player loves to assist his teammates, then a medic is the kind for him. If the player loves to be a hulking unstoppable beast, then the heavy weapons guys is perfect for that. Each class is great for a certain role and through teamwork, each role can be fulfilled and the objective can be completed.
Currently there are only six official maps so the content may seem small, but the Team Fortress 2 modding community is bound to fill in the slack. Valve frequently and consistently releases patches and fixes and updates for the game and te mod community already has a plethora of user made maps meaning that the variety of the game could never end.
While other "team" oriented multiplayer shooters focus on how well a group of individuals can perform, Team Fortress 2 focuses on how well a group of individuals can perform, together.