If you're looking for change, I think in a sense you're sort of out of luck. CoD is the same every time because it has a large fan base who loves that type of gameplay and doesn't want it to change much asides from a couple twists and new maps to keep it interesting. Also the prestige race is still exciting for some people too.
But, for some, I think ghosts will be the CoD they've been waiting for. Apparently you can't quick scope in it. If they got rid of quick scoping, I'd imagine the gameplay might be a bit more strategic and thought out as opposed to say mw3.
It seems that the people who dislike quick scoping, dislike cod run and gun gameplay and lean more towards games like bf4.
But yea, CoD will never change dramatically like you might be hoping for. If it did change that much it'd be a new game and a new title. The best you can hope for, are a couple new dinky features and creataclass layouts, upgraded engines and graphics, and stellar maps.