User blog comment:Damac1214/Opinion: Why I truly am excited for Black Ops II/@comment-4122733-20121003073241/@comment-1263839-20121003174313

The average lifespan of a modern Call of Duty game is about 2-3 years.

They have 2 years of activity (albeit in the second it starts to drop except in the grand world of CoD 4 and WaW co-existing peacefully), and in the third hackers start to come in. After that the game dies.