This week, Oprah Winfrey's mammoth afternoon talk show began its 24th season with a fun "tribute" to viral culture during a Kickoff Party in Chicago's "Magnificent Mile." During a large outdoor performance by the Black Eyed Peas, a flash mob consisting of 21,000 of Oprah's biggest fans broke out in coordinated dance to the music group's summer smash, 'I Gotta Feeling.' You know how much we love flash mobs! We, along with the mighty O herself, are still trying to figure out how on earth they coordinated all those folks. Video below.