Call of Duty: Ghosts will add a number of new features to the Call of Duty online multiplayer experience.
Thanks to the new, upgraded engine being used (all Call of Duty games from Call of Duty 4 onwards have used the same engine), multiplayer maps will be significantly improved graphically. There will be more attention to detail, improved textures, and better use of lighting.
Character customisation is set to be more wide-ranging in Ghosts as well. And your character will in general be much more agile - you will be able to lean around cover, slide across the floor and more realistically interact with the game environment.