Britney Spears is back

As Britney Spears prepares to launch her seventh studio album "Femme Fatale" on Tuesday, the pop star faces keen competition from Lady Gaga, Katie Perry and Rihanna, who reign atop Billboard's Hot 100 singles ranking. Photo shows Britney Spears performing on ABC's "Good Morning America" show at the Bill Graham Civic Auditorium in San Francisco on Sunday, March 27, 2011.