Katy Perry's style has certainly changed since she left Russell Brand. And now that she's dating John Mayer, it's not much of an improvement. Over the past season Katy went from kooky and eclectic to monochromatic and demure. When Katy was with Russell she sported fun pink wigs, blue wigs, smurf dresses and now the 27 year old is sporting fedoras, dark natural hair and a boho chic wardrobe. She's actually starting to dress like her new beau John Mayer these days.