Organizers of the 40th anniversary Glastonbury Festival, scheduled for June 25th, 2010, have announced that U2 will headline the festival. It will mark the Irish band's first festival appearance in 25 years. The festival lines up perfectly with a break in the band's hectic schedule on their hugely successful 360 Tour. Tickets for the festival, 177,500 of them, sold out in less than 24 hours before any of the performing artists were even announced.