I liked Call of Duty World at War the most. But ever since they started doing all this futuristic stuff, I've despised it. I was hoping they would do a second World at War instead of BO3, but nope. From what I've heard, BO3 is like Titan Fall.
I dislike the game, but I see why so many like it, the skill curve is very slight, if any at all. I get the fact that its got good graphics and such, but the game just is too easy for me. I personally prefer CSGO or GMOD for my entertainment.