Travel What happens in Vegas, stays in Vegas: New Sin City slogan to be revealed in Grammys ad January 17, 2020 Ed Komenda, Reno Gazette Journal Comments Off on What happens in Vegas, stays in Vegas: New Sin City slogan to be revealed in Grammys ad Las Vegas' "What happens here, stays here" mantra is getting an update. A commercial revealing Sin City's new slogan will air during the Grammys.