Mumford & Sons' debut was a surprising breakout record: A bunch of Pogues-loving Brits dressed like they just galloped in from the set of Little House on the Prairie suddenly became the next Coldplay. But maybe we shouldn't have been surprised; where most folk music goes for intimacy, M&S go for arena grandeur. They've jokingly described their forthcoming LP, Babel, as "Black Sabbath meets Nick Drake," and this single shades in that direction with its hammer-down forlornness and road-weary lyrics about living through "days of dust." But then the Mummies serve up some bread and butter on the chorus, a Bono-big pledge of fidelity perfect for misty-eyed singalongs.

Listen to "I Will Wait":

“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."