Call of Duty: Ghosts confirmed to have maximum 9 vs. 9 in multiplayer
You know what the next-gen Call of Duty: Ghosts doesn't allow? More players in an online match. During Ali-A's unboxing of the Xbox One Prestige Edition, he pointed out that the back of the box said 2 to 18 players online. So 9 versus 9 is still the maximum amount of players in a match.
To me, that's not a big deal. If I want huge maps that turn into slugfests with a massive amount of players, I'll play Battlefield. Call of Duty's maps are meant for smaller teams. 18 already feels a little crowded; any more really wouldn't feel like a Call of Duty title. I don't think it's that Infinity Ward can't have more than 9 versus 9 at one time. It has to be a design choice. Just because it's a next-gen console with dedicated servers doesn't mean that there needs to be more players allowed to play in a match at a time.