Jennifer Lopez and Casper Leave "Letterman" after Jen's Promotion

Singer Jennifer Lopez stopped by the set of "David Letterman" to promote the new show that she and ex-husband Marc Anthony will be working together on titled "¡Q'Viva! The Chosen" in New York, New York on January 30, 2012. "Q'Viva!" is similar to Jen's other hosting job on "American Idol" where she and the other judges will select the best Latin-American talent from the contestants.