Since the game is based after a band, it is only natural that The Naked Brothers Band is a rhythm game. All of the music in the game is from the band, and while it wasn't something I would listen to, fans will enjoy hearing their favorites. Considering the system, the quality of the music is decent; it isn't as good as Elite Beat Agents, but I've heard much, much worse on the system. Voices are a little garbled, though not so much that you can't understand the words to the song. However, it is a little hard to hear some of the instrumental stuff. It is still easy enough to catch the beat and play along with the rhythm, though.
As for the visuals, they are sort of just there. Everything is incredibly flat with little in the way of animation. There are, however, a few nice additions like the ability to update your band's look and some nice pyrotechnic effects. But, like any rhythm game, most of your attention is locked in on the scrolling play bar, so everything else isn't of much importance in the long run.