Cheating and griefing or other threats to fair play will not be tolerated. You are responsible for how your account is used. The use of cheats, including third-party software, is unacceptable. Exploiting bugs or engaging in any activity that grants an unfair advantage is considered cheating.
Ranked Play is the official competitive 4v4 Multiplayer experience for Modern Warfare II, using the official rules, restrictions, maps, and modes from the Call of Duty League, which can be read here. Whenever the Call of Duty League rules are updated, expect changes to the Ranked Play rules to follow suit.