I’ll confess right out that I have little patience for the direct application of popular music items to liturgy. In the time it would take me to locate a rare exception, I could write a new song myself. One basic problem is that U2′s music, though inspiring to many fans (including my daughter) is, like opera and choral masterworks (also inspiring to many fans like me), essentially a performance idiom.
I’m sympathetic to church leaders who try to impart a certain verve to worship. It’s better than languishing in outdated traditions, crossing one’s fingers and hoping the Holy Spirit will provide.
I suspect that discerning U2 fans would be attracted to any church or religious venue that remained authentic to form and message. And really, seekers are often discerning enough to ferret out that authenticity.