Late night will never be the same. Jimmy Fallon took the stage Monday night for his big debut as new host of The Tonight Show. Jay Leno's replacement kicked off the show with a heartfelt monologue, then he got heckled by a very unsuspecting member of the audience. Of course, Jimmy was visited throughout the show by a parade of celebrity guests. Our favorite part of the show? You'll have to watch to find out! On Becca: Vince Camuto top