With their injury-delayed 360° Tour finally set to resume Friday in Turin, Italy, the members of U2 rehearsed Sunday onstage at the Stadio Olimpico di Torino — and treated fans assembled outside the stadium’s gates to what is believed to be a brand-new song.

Nearly two months after scrubbing its North American summer tour, U2 today announced 16 rescheduled dates for the 360° Tour’s second stateside leg, which now will open May 21, 2011, in Denver and run through July 23, 2011, in Minneapolis.

While U2 was knocked out of its first-ever Glastonbury headlining slot by Bono’s recent tour-scuttling back surgery, fans still got a taste of the Irish megaband tonight when The Edge joined Muse for an encore of the all-time classic ‘Where the Streets Have No Name.’

With Bono’s recovery from back surgery expected to take at least eight weeks, U2 today canceled its first-ever Glastonbury appearance and pushed this summer’s North American leg of its massive 360° Tour to sometime in 2011.

U2 today postponed the opening date of the second U.S. leg of its monstrous 360° Tour — June 3 in Salt Lake City — after Bono this morning underwent emergency surgery in Munich ‘for an injury sustained during tour preparation training,’ according to the band’s official site.

Today we commemorate Bono’s 50th birthday, knowing full well the frontman, and U2 itself, are somewhat divisive forces in the annals of ’80s college rock. Check out the band’s epic performance of ‘Sunday Bloody Sunday’ from ‘Rattle and Hum.’