OK! MagazineEnd of the World May 21st Music Playlist: REM, Britney Spears, Muse & More!OK! MagazineAccording to Christian radio broadcaster Harold Camping, Judgment Day will be upon us on May 21, 2011. The Web has exploded in talks about the end of the world, so while you wait, why not listen to an “end of the world” playlist. …