The challenge for Antony Hegarty is just how best to use that quivering, purring, sobbing, ecstatic, altogether original voice. Though he's a great disco diva (see Hercules and Love Affair's 2008 "Blind"), his Johnsons work tends toward the sepulchral. On their fourth set, ghosts still haunt Hegarty's piano-and-string-sketched chamber songs. But there's a new ease to his musical language here, and playfulness, too. He sings a breathtaking duet with Björk in Icelandic ("Flétta"). And the left hook is "Thank You for Your Love," which fully realizes the Southern soul sound Hegarty has flirted with on older tracks like "Aeon" and "Fistful of Love." The further afield dude wanders, the better he gets.

“I'm Yours”

Jason Mraz re-emerged after his disappointing second album with this lead single, a Jack Johnson-esque ditty about giving yourself fully to someone else. The success of the reggae-tinged song (it earned two Grammy nods and a spot on the Billboard singles chart for well over a year) was something the folk-pop singer never predicted when he wrote it in 15 minutes at home. "I played a happy-hippie chord progression that would probably work without 50 different Bob Marley songs," he told Rolling Stone. "I thought, 'It's too novelty. This is a nursery rhyme,'" concluding that "you can never guess what's gonna be a hit."