Lady Gaga, Zac Brown Added To GRAMMY Sinatra TributeHarry Connick Jr. and Celine Dion have also been added to the special.
Foo Fighters & Zac Brown Cover Black Sabbath's 'War Pigs' on 'Letterman': WatchThe Foo Fighters kicked off their week-long residency at The Late Show with David Letterman by wearing their metal heart on their sleeves.
Elton, Mumford Lead Levon Helm GRAMMY Tribute
