In a Billboard interview this week, Katy Perry offers a few predictions for her career: “I love Madonna to death, but she’s never going to give me that damn baton. I’ll probably turn into more of a Joni Mitchell.†Tell that to her new single, which is so nineties that it could be sung by a cone bra (with lasers or something shooting out of it, KP-style). Here’s “Walking on Air,†which will make you shimmy despite yourself. Prism is out next month.