01 � Led Zeppelin: The band will launch a full catalog reissue campaign this year, with newly-remastered albums set to feature a companion disc of unreleased material, according to Jimmy Page.

02 � U2: The band will return this spring with the follow-up to 2009's "No Line On The Horizon." Danger Mouse has been producing the project, and reports indicate U2 are currently shopping for brand partners to announce the album via a Super Bowl commercial.

03 � Foo Fighters: Dave Grohl & Co. are working on the follow-up to 2011's "Wasting Light." Butch Vig is producing the project, which Grohl says is being made in a way that no one's ever done before�without elaborating or giving that secret away.

04 � Metallica: The metal icons have been busy touring the past few years while stockpiling riffs for future use, and they say they're planning to hit the studio in 2014. At least one new Metallica track will surface this year, as the group has committed to playing one new tune on their summer "Metallica By Request" tour of Europe�while fans vote to select the other 17 songs for each concert.