Only on the "CBS This Morning" podcast, Kevin Allocca, author of "Videocracy: How YouTube Is Changing The World With Double Rainbows, Singing Foxes, And Other Trends We Can't Stop Watching," joins "CBS This Morning" co-host Gayle King to discuss what makes a video successful on YouTube. Allocca, also YouTube's Head of Culture and Trends, explains the challenge of writing a book about online videos and the value people extricate from videos. He also shares his definition of a viral video and the most popular how-to-video.