I feel that the music of the past two albums was necessary for the band, to sort of remind themselves of what U2 is, but it is not in their nature to just be a rock and roll band that plugs in and plays hard. I believe that after the Vertigo tour they really got a hunger to find something new that no one has heard before. I believe we heard this on Pop, and I believe we will hear this on the new album

just a thought though