If you partied in the ’00s, you already know eclecticism ruled the dance floor, as the hard lines between ’90s genres were basically being wrecking-balled by the rise of downloads and streaming. The ability of the era's songs to inspire booty-shaking is in no danger of expiring; they still feel brash, with the sheen of a familiar style undergoing a thrilling shift. To wit, teen pop went urban, as producers like Timbaland gave edge to ex-Mouseketeers such as Justin Timberlake. Urban became mainstream as people once known as collaborators—Beyoncé and Kanye West—claimed their spotlight with larger-than-life production. And the mainstream got weirder as artists like Outkast, M.I.A. and Lady Gaga introduced a sense of free-wheeling auteurism. It’s that last development—along with the rise of reggaetón—that pointed most clearly to where the party headed in the ’10s as the stylistic meld continued and stars got ever bolder in embracing their odder ideas.