U2 band members "The Edge" (L) and Bono play on the roof of the BBC Broadcasting House building in London February 27, 2009. Irish band U2 releases its 12th studio album on Monday, and while reviews are generally glowing, critics argue that lead singer Bono's dual role as rock star and campaigning "saviour" may be meddling with the music. REUTERS/Stephen Hird (BRITAIN)