Rebecca Black's Buzz Cools on Social 50 Chart

A Year of Social 50 Breakthroughs, With Rebecca Black, Karmin & More

Rebecca Black's social buzz -- as measured on the Social 50 chart -- continues to erode as the singer slips 12-22 on this week's tally. The famed "Friday" singer entered the list at a record high of No. 9 three weeks ago, but her online chatter has since -- naturally -- waned.

The Social 50 ranks the most active artists on the world's leading social networking sites -- YouTube, Vevo, Facebook, Twitter, MySpace and iLike -- using a formula blending weekly additions of friends/fans/followers along with weekly artist page views and weekly song plays.

Though Black was up 48% in week-over-week new Twitter followers, she fell by 32% in YouTube views. Through April 6, her "Friday" clip had been seen 86.8 million times on the website since it was loaded to the site on Feb. 10.

Rebecca Black Spoofs 'Friday' Success in Funny or Die Clip

Back in the top 10, Lady Gaga and Justin Bieber hold down the Nos. 1 and 2 positions, respectively, while Eminem shuffles 4-3 and Katy Perry jumps 6-4. Rihanna slips 3-5, Shakira slips 5-6 and Akon is steady at No. 7. Lil Wayne and the Black Eyed Peas both rise one spot, climbing to Nos. 8 and 9, respectively.

Rounding out the top 10 is Britney Spears, who rides the wave of release-week buzz from her "Femme Fatale" album to a four spot jump to No. 10. Spears saw a 3% rise in Twitter followers and a 52% increase in YouTube views.

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Outside the top 10, Kanye West motors 40-18 with a 40% increase in YouTube views. West was in the news last week thanks to the debut of Perry's elaborate music video for "E.T.," in which he guest stars.

Re-entering the list this week are Radiohead (No. 33), Christina Grimmie (No. 37), Jessie J (No. 46), Boyce Avenue (No. 47) and Dr. Dre (No. 48).

Making their chart debuts are Justice (No. 43) and Pink Floyd (No. 50). The former likely arrives thanks to the recent debut of its new single, "Civilization," from its forthcoming new studio album.