JUST ADDED: 5 Seconds of Summer will be rocking the stage at this year's iHeartRadio Music Festival Village in Las Vegas! The band sat down with Ryan Seacrest to break the news. Click here to buy your tickets now, before they sell out!
Jimmy Fallon does it again! You've seen the Brian Williams rapping supper cuts before...but what series about anything hip-hop would be complete without Sir-Mix-A-Lot's 'Baby Got Back'? That's right...it wouldn't.