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Miley Cyrus

HOLLYWOOD, CA - DECEMBER 08: Singer Miley Cyrus performs at Borgore's "Christmas Creampies" concert at Henry Fonda Theater on December 8, 2012 in Hollywood, California. (Photo by Chelsea Lauren/WireImage)

What Were They Thinking?!

This week's worst-dressed crew includes Katy Perry, Kristen Stewart, and Kim Kardashian. -- By Matt Whitfield, Yahoo! Staff