British folk rock sensation Mumford & Sons revealed on Wednesday that they have completed the recording of their sophomore album, though tyhey indicated that there's no guarantee the album will ever be heard.  "We're done recording it," keyboardist Ben Lovett said in an interview with NME magazine, "but if we listen back while we're mixing and discover it's shit, we'll just start again. We're not going to put it out until it's good enough."  Mumford & Sons' 2009 debut "Sigh No More" has sold more than 2.2 million copies since its release, according to Nielsen SoundScan figures, and racked up a handful of Grammy nominations including nods for Record of the Year and Song of the Year for their hit, "The Cave."