Flash Mob America, which stages events at corporate conferences and trade shows, began in 2009 after a group of friends put on a flash-mob tribute to Michael Jackson, which went viral.

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Likely working in its favor: host network CBS strived to bridge generations (and capture a broader audience) with a series of duets, including Lady Gaga and Elton John and Taylor Swift and Stevie Nicks, as well as a 3-D tribute to the late Michael Jackson.

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He also paid tribute to the late Michael Jackson with a DJ set in the middle.

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As well as the roar of 70, 000-plus red-shirted rugby fans cheering on Wales, the stadium has played host to gigs including Paul McCartney, a Michael Jackson tribute concert and other sporting events.

BBC: Gerry Toms