I'm a Call of Duty player myself, and have been since Call of Duty 4: Modern Warfare. Therefore, I can fully understand the appeal of these games. The single player offers some of the most exhilarating action set-pieces and the multiplayer is addictive. Call of Duty changed the face of military based first-person shooters, to the extent that every FPS now follows their formula. I never thought there would be a first-person shooter series that could rival the Call of Duty experience until I played Battlefield 3.
Many would argue that these two games are for two different types of gamer. The reason being that Call of Duty is designed for fast paced arena style action, and Battlefield 3 is designed for slow paced strategic gameplay. For that reason Call of Duty is more accessible to all types of gamers, whether casual or hardcore.
This is the exact reason why Call of Duty continues to become more dumbed down and frustrating to play. Meanwhile, Battlefield 3 is pleasing those who truly wish to know what it means to experience war. So here are a few reasons that support my opinion on why Battlefield is a better series than Call of Duty.