Rihanna topples Shakira from fourth place on Twitter

Rihanna has overtaken Shakira on Twitter to become the fourth most popular person on the microblogging site behind Lady Gaga, Justin Bieber and Katy Perry.

Rihanna now has more than 14.8 million fans to her name while Shakira is sitting on a total of over 14.7 million fans.

Rihanna is not the only one making her way up the Twitter rankings this week. Fellow pop star Britney Spears has dislodged socialite and reality TV star Kim Kardashian from sixth place on the chart.

Lady Gaga tweeted that she has been busy rehearsing for her new tour. She posted "The new show is easily the most fun I've had on stage in ages, + YOU'RE not even there yet! IM GONNA DIE OF EXCITEMENT. Throw ice if i do."

Country musician Taylor Swift has been talking about her most recent tour too. She shared pictures of her trip around Australia with her Twitter fans.

Sina Weibo users Yang Mi, Xie Na and He Jiong all hit important follower milestones during the week. Yang Mi and Xie Na both passed 15 million fans and He Jiong topped 14 million fans.

Third party estimates put Twitter at more than 500 million registered users. Sina reported that it had more than 300 million registered users on Sina Weibo in February 2012.

Most popular people on Twitter:

Lady Gaga (20,583,416 followers)

Justin Bieber (18,343,591)

Katy Perry (15,978,204)

Rihanna (14,821,690)

Shakira (14,748,562)

Britney Spears (13,919,789)

Kim Kardashian (13,865,711)

Barack Obama (12,960,220)

Taylor Swift (11,611,285)

Selena Gomez (10,849,921)

Most popular people on Sina's microblog (Weibo):

Yao Chen (17,947,845 followers)

Dee Hsu (17,337,365)

Yang Mi (15,163,557)

Xie Na (15,031,572)

Kevin Tsai (14,668,423)

Zhao Wei (14,395,361)

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Leeh om Wang (14,295,563)

He Jiong (14,022,354)

Li Bingbing (12,993,184)

Chen Kun (12,449,601)

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