User blog comment:Callofduty4/Playstation Network users to get double XP weekend/@comment-3122254-20110518102158/@comment-1330942-20110518153415

It's a game mode where you can only play on Nuketown. Instead of voting for the next map (which will ALWAYS be nuketown), you vote for the game mode (S&D, TDM, demol., ...) Thats what nuketown 24/7 is :)