Yeah, Battlefield 3 is far more realistic than COD but is also a lot harder. Killzone 3 has a pretty fun multiplayer imo and you can just buy the multiplayer component at the PS Store. MW3 is fun and there are a lot of people playing the game.
You should also consider getting Black Ops. If you're not that great at fps multiplayer, then I think MW3 will have an easier learning curve for you.
Well, I have both BF3 and MW3 so I don't know about killzone, but BF3 is more slow paced, vehicle epic battles, and mw3 is mostly close quaters, and recently full of quickscopers and trickshotters in gamemodes such as search on destroy. I'd personally go with whatever kind of battles you like, If you like to mess around and not play serious something, go for battlefield 3 If you wanna really rank up and get the job done, go for MW3 I personally go with BF3.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.