In this week’s magazine, Tad Friend writes about the celebrities of YouTube and Vine, who gather millions of fans—and sometimes millions of dollars—with their viral online videos, even if most of us have never heard of them. Friend and Kelefa Sanneh, a staff writer who frequently covers pop culture, join Michael Agger, the culture editor of The New Yorker’s Web site, on this week’s Out Loud podcast to discuss the “Beatlemania-type receptions” of these figures, the economy of YouTube fame, and what the phenomenon reveals about the nature of modern celebrity. Friend says, “In the old world, someone like Kim Kardashian, everyone knew a little bit about her.... In the future, there will be people who are incredibly famous and deeply well known to a small group of people, but not known to everyone else.”