User blog comment:Damac1214/Modern Warfare 4 supposedly leaked, Captain Price to return (UPDATE - Confirmed False)/@comment-71.125.15.146-20121102151011/@comment-1854594-20121105172447

They stopped numbering them because say if you wanted someone to play Call of Duty: Black Ops you could tell him to put in Black Ops instead of saying Call of Duty 7. I would know what you were talking about if you mentioned Call of Duty 7 but not everyone does, Black Ops makes it much more identifiable.