In its full list, Time gives the first position to Wael Ghonim, Google's Middle East marketing director who was one of the driving forces behind the revolution in Egypt in January.
Kim Clijsters is one of only three sportsmen or sportswomen in the top 100. The others are the Indian cricket player Mahendra Singh Dhoni and FC Barcelona's football star Lionel Messi.
Former tennis champion Martina Navratilova explains Kim Clijsters' excellent score on the Time website. "After her daughter Jada was born in 2008, Kim decided to make a comeback and she surpassed the expectations. She posted back-to-back victories at the US Open and took first place on the world rankings in female tennis."
However, good results are only part of the explanation. It's also about image and what she does outside the court. "She keeps her feet on the ground, and when the players decide to hold a charity, she is the first one to take part."