U2 played almost as many songs per show on 360 as Springsteen plays on his current tour.
Springsteen's probably playing about 3-4 songs more per night (From memory, U2 played 23 most nights with one as the very-very-short MLK/Scarlet) and it's lasting a good 30-45 mins longer.
Springsteen's shows though have always had a improvisational element to parts of the setlist that U2 has never brought live.
I think its much easier for Springsteen and the E Streeters to randomly play a song out of their catalog than it is for U2.
Bruce pulled out My Love Will Not Let You Down at my Working on a Dream concert, and it sounded like they've been playing it all tour.
U2 played an improvisational Love Rescue Me after All I Want is You, and it sounded like they could barely keep afloat.
I blame U2's lack of improvisational skills on Edge actually. Since the band has so many different guitar sounds, its impossible for him to randomly float to different songs here and there because of equipment they might need for said song. That and Bono is terrible at remembering lyrics.