The music is fine. There are tracks I like, and tracks I don't like, but overall it's just okay. None of it is really "bad," but compared to previous games I feel like the hourly themes are somewhat lacking the catchiness and, er, wildness of the old ones.
But, at the same time that's not really a bad thing, because the music has changed along with the gameplay style... yeah, I mean that.
Beautifying your town wasn't really the point back then, it was forming relationships and improving your home, mainly. I was only introduced to this game almost a year ago, and even I could gather that, I felt closer to my animals in those games. They had more character and more things to say. But now with the advent of PWPs and more customization options than ever before, the game is more like a sandbox.
I'm not complaining though. I love New Leaf so much. I just wish the spirit of the older games and the feeling of community was stronger in it.
Now, what the hell does this have to do with music? Well, I believe that if the aspects of beautifying your town AND befriending your neighbors were used to their full potential in the next game we might get a happy medium; some peaceful, beautiful music with a sense of fun and adventure to it.
That's been mulling over in my head for a while now, sorry about the long post.