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Kate Bosworth

NEW YORK, NY - NOVEMBER 28: Kate Bosworth attends the Target Neiman Marcus Holiday Collection launch event on November 28, 2012 in New York City. (Photo by Dimitrios Kambouris/WireImage)

What Were They Thinking?!

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