Michelle Obama Named Most Powerful Woman in the World

U.S. First Lady Michelle Obama was named in the top spot on Forbes' list of the World's 100 Most Powerful Women Wednesday-- a list dominated by American celebrities and politicians.

The top 10 reveals three powerhouse black women -- Obama, talk show host and media mogul Oprah Winfrey at number three, and singer Beyonce Knowles at number nine.

Last year's number one, German Chancellor Angela Merkel, dropped to four on the list, just ahead of U.S. Secretary of State Hillary Clinton who jumped to the number five spot this year, up from number 36 last year.

Forbes said its judging criteria for this year's index shifted away from its traditional calculations of economic influence and international media coverage.

Instead the magazine focused on entrepreneurship and the level of creative influence these women had on the world at large.

Clinton was just ahead of singer Lady Gaga -- number seven -- who has a daily audience of 25 million on Facebook and Twitter and earns $62 million a year.

Lady Gaga, whose real name is Stefani Germanotta, was the youngest person on the list. The 24-year-old joined 29-year-old Knowles and Serena Williams, 28, as the only people aged under 30 among the top 100.

Williams, currently the number one tennis player in the world, was listed at number 55, a few spots ahead of her sister Venus Williams at 60.

Queen Elizabeth II was the highest ranked -- and only -- Brit on the list at 40.

Australia's first female prime minister, Julia Gillard, made the list for the first time at number 58, but the boss of Westpac, one of the nation's biggest banks, Gail Kelly, was the top Aussie in the 8th spot.

"The women on our list, through their respective realms of power and influence, are shaping many of the agenda-setting conversations of our day," Moira Forbes, the vice president and publisher of Forbes Woman, said.

"They have built companies and brands, sometimes by non-traditional means, and they have broken through gender barriers in areas of commerce, politics, sports and media."