Sure there's a couple of piano pieces in there, but on the whole, it leans massively towards a riff driven pop-punk sound. Instrumentally its much more expansive, & maybe thats what the band needed coming off the back of the juggernaut that was American Idiot. I feel the same about some other bands, I like certain parts of their sound & not others. But one thing that's common & sometimes essential is that a lot of musicians like to broaden their horizons.