Katharine McPhee was a Smash last night on American Idol, thanks in part to a brand new haircut! The AI alumna chopped her ombre shoulder-skimming waves into a chin-length bob, which she debuted during her performance with One Republic. When we last spoke to McPhee, she told InStyle.com that her style inspiration was Diane Keaton, so it's no surprise to see the star working her icon's signature 'do. But do you prefer Katharine's short look? Tell us by voting in the poll below!