I mean that I've noticed some difficulties and some slight off-tune singing. I know singing along to kareokes or orchestras is quite difficult, and even more when it's a swing/jazz song, that use to have seventh and diminished chords that make even harder to sing in tune. His vocal strength and stage pressence are still superb though.
wow...quite satisfied with Bono right now! He actually sounds like the Zoo TV era which I thought would not happen any more...let's hope the album is as good.