PSY Photos: 'Gangnam Style' Invades America
PSY performed in a snappy green blazer and then sat down to chat with the hosts of NBC's "Today" show at Rockefeller Plaza on Sept. 14.

Busy week keeps the 'Gangnam Style' star in the social driver's seat, while Mumford & Sons also creep up the chart.

PSY continues to dominate Billboard's Social 50 chart, keeping a firm foothold in the No. 1 spot for a fifth straight week. With so many television and festival appearances directing online attention, one wonders when he finds time to sleep.

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The Social 50 chart ranks the most popular artists on YouTube, Vevo, Facebook, Twitter and MySpace, using a formula that blends weekly additions of friends/fans/followers along with weekly artist page views and weekly song plays.

Here is a list of just some of the notable PSY happenings in this past week:

- A second appearance on "The Ellen Degeneres Show."
- Guest slot at the iHeartRadio Music Festival in Las Vegas.
- He made the Guinness Book of World Records for the most liked YouTube video of all time.
- He met Bon Jovi and LMFAO's Redfoo.
- "Gangnam Style" hit No. 2 on the Hot 100 and No. 1 in the iTunes Music Store in 31 countries.
- He stopped by "Chelsea Lately" and appeared on "Extra" with Mario Lopez to talk about partying with Usher.
- Lastly, he updated his Twitter to display a new and simpler "Gangnam Style"-oriented background.

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Television appearances of this caliber have helped PSY build his audience at an incredible rate. For the fifth week in a row he's experienced double digit follower acquisition growth, with a 20% rate of increase bringing in a whopping 180,000 Facebook fans and 104,000 Twitter followers. The now-famous video, while decelerating in week-to-week viewership by 30%, still gains an incredible 39 million views in just this past week.

As for the rest of the top 10, Taylor Swift remains at No. 2 as One Direction rises (4-3) and Katy Perry bumps up (6-4). Skrillex is steadfast at No. 5, while Justin Bieber swings (7-6), causing Rihanna to drop (3-7). Jennifer Lopez holds at No. 8, as does Lady Gaga at No. 10. Finally, Cimorelli pokes back into the top 10, rising two slots to No. 9.

Elsewhere on the chart, indie folk rock band Mumford and Sons experiences a 32-24 jump as online activity surrounding their newest release, "Babel," propels them up the tally. With a "Live at Letterman" performance and an appearance on "Saturday Night Live" the band received a great amount of attention online. Mumford and Sons gained 25,000 new Facebook fans and 9,000 new Twitter followers, equating to a 52% increase in overall weekly follower growth.

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Last week saw the release of "Kiss," Carly Rae Jepsen's new album, and in turn, the singer zoom 21-13 on the Social 50. The online popularity of her single "Call Me Maybe" helped usher the album to a No. 6 debut on the Billboard 200. Additionally, her song "Beautiful," a duet with Justin Bieber, debuted at No. 87 on the Billboard Hot 100. She gained 120,000 Facebook fans during the charting week (12% more than last) and 123,000 followers on Twitter (a 6% decline).

Hugely popular YouTube violinist Lindsey Stirling makes the ever-increasing list of artists born on YouTube who take their careers offline as she released her debut album during the charting week. The self-titled release debuts at No. 81 on the Billboard 200 and No. 1 on Classical Crossover, while subsequently dominating Classical Digital Songs with every single song from the album making the chart. On September 18 she released a YouTube video for "Elements," one of the singles from the release, which racked up over 1.2 million views. She rises 42-27 on the Social 50 this week after adding 49,000 fans to her overall fan base.