The CoD games have always had short single-player modes. But that's fine, really; that just means that the action doesn't grow stale before the game ends.
But, yep. I wouldn't pay full price for one, since I don't care about online modes.
"'Casual games' are something the 'Game Industry' invented to explain away the Wii success instead of actually listening or looking at what Nintendo did. There is no 'casual strategy' from Nintendo. 'Accessible strategy', yes, but ‘casual gamers’ is just the 'Game Industry''s polite way of saying what they feel: 'retarded gamers'."
-Sean Malstrom