Britney Spears will fill the July 9 Marcus Amphitheater spot for Summerfest 2011. She's promoting her latest work titled Femme Fatal. Some say that the album is the best in years. It's a darker type of disk, that's for sure. It's not without songs that you can dance to, but certainly a shade of Britney that we have not seen before. Tickets go on sale May 21.