Halo multiplayer is absolutely horrible. When I shoot someone, they should die. End of story. Halo hopping is not diversity. It's stupid. Again, one of my favorite co-op experiences, especially for a sci-fi shooter, which isn't normally my thing.
I enjoy BF3. My point in talking about it is that its not polished. I have never fallen out of the map in a CoD game or had players simply become invisible. This is a far too frequent occurence in BF3. So you can't really go and say it's more adult or realistic or whatever. In reality, it's highly unlikely an invisible man is going to shoot me whilst I am clipping through the ground towards the center of the earth. I would say it's at least 20% more likely Mitt Romney can be president of the United States.