Taylor Swift's duets with her musical predecessors haven't always been well-received -- she was famously off-key during her performance of "Rhiannon" at the Grammys with Stevie Nicks a few years ago.
But the 23-year-old starlet tried again on Saturday night, inviting legendary singer-songwriter Carly Simon to join her onstage for a rendition of "You're So Vain," the 1972 hit about an egotistical mystery man.