Gaga posted a 15% jump in new weekly Twitter followers while she also posted handsome increases in views on both her official YouTube and Vevo channels. While Bieber was up in views on Vevo, he was down in most other measured metrics, thus assisting in his vacating of the top slot.
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.
Meanwhile, Chris Brown vaults 27-14 while Jennifer Lopez debuts at No. 31. Both stars were in the news the past week for different reasons. Alleged self-shot racy photos of Brown leaked to the Web -- perhaps helping raise his social chatter (he's up 18% in new Twitter followers), while Lopez' video premiere for "On the Floor" fired up fans (her Vevo views went through the roof: up by more than 1,000%).
Back in the top 10, it's almost another week of musical chairs as many familiar acts rotate positions. Rihanna and Eminem are steady at Nos. 3 and 4, while Shakira is up three slots to No. 5. Katy Perry and the Black Eyed Peas both descend a slot apiece -- they are at Nos. 6 and 7, respectively. Ludacris returns to the top 10, rising 14-8, as does Avril Lavigne (11-9). Closing out the top 10 is Akon, falling three rungs to No. 10.