On eve of expected IPO, Twitter has new top bird

Andrew Harrer | Bloomberg | Getty Images

Say it ain't so, Beliebers.

Just days before Twitter's expected IPO on the New York Stock Exchange, singer Katy Perry (@KatyPerry) has become the service's most popular user, taking the title away from fellow artist Justin Bieber (@JustinBieber).

With 46.48 million followers, Perry edged in front of Bieber's 46.47 million Sunday afternoon, claiming the top spot in terms of fans on the seven-year-old platform. (Bieber sat in first place for nine months after bumping Lady GaGa out of the ranking which she dwelled in comfortably for two years.)

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While some in the social media space will advise you not to equate the amount of followers a user has with a level of popularity, "Twitter's most followed user" is a ranking held in high esteem. Just four years ago, actor Ashton Kutcher made headlines when he beat out CNN to being the first Twitter user with one million followers.

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Those wary of the follower metric will quicker glance at a user's "Klout score," – a number from 1 to 100 that signifies how much engagement a particular account is receiving.

Although Perry may have more followers than Bieber, Klout shows that both singers have a score of 95, a respectable number that suggests tremendous influence. Furthermore, Bieber's tweets generally receive more retweets and favorites than Perry's, based on a review by CNBC.

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The question to ask though is how many of the combined 92 million accounts are real?

StatusPeople, a tool that determines how many of a Twitter user's followers are fake, says 41% of Bieber's followers are not legitimate, while Perry has a 'Faker Score' of 52%.

Fans of Bieber were quick to point out this statistic when Perry was crowned on Sunday. "Justin's followers are real unlike Katy Perry's," Twitter user @PurpleBieber wrote.

Another user named @IgnantBieber joked, "Katy Perry could make a breakfast menu with all those egg followers."

Seven of the ten most followed accounts belong to artists in the music industry; the three others are @Instagram, @YouTube and President @BarackObama.

— By CNBC's Eli Langer. Follow him on Twitter @EliLanger