Picking up on the song really isn't a book vs. non book thing, it is a perception/music thing. While the books have the lyrics and state when the song is being sung or played it is not like you know what that sounds like. Sure, I knew the meaning of the song before the show started, but it wasn't really until late last season (because of a podcast) that I started hearing and thinking about the music in the show. The non book reader of the podcast is very focused on music in film and TV so he brought up the musical cues and hints that were going on ie - Rains of Castemere and Melisandre's theme. Just like me, the other person on the podcast, who had read all the books, hadn't picked up on those. It's one of those things that you start to notice once it is pointed out to you, but I completely understand people not picking up on it naturally.