We don't yet know whether or not Call of Duty: Modern Warfare 4 will feature skill-based matchmaking (SBMM), but one Infinity Ward lead promises the devs will be "transparent" about the situation soon.
SBMM is a divisive topic within the Call of Duty player base – while as the name suggests, it's a system that aims to match players with similar skill levels against each other for a more balanced experience, some argue that doing so makes the game feel less casual and more sweaty, removing the joy from matches where you're head and shoulders above the competition.