During last nights JJP session The Hobbit was revealed and along with it we heard some of the music used in the game from Two Steps From Hell. I've been listening to this group for about a year and they do some amazing work.
The song heard during Smaug Multiball is "Moving Mountains" from the Invincible album.
You can hear the track above in the video below around 50 seconds in.
http://www.youtube.com/embed/XVzlgnhsPT4?autoplay=1&rel=0
It looks like JJP is licensing some of Two Steps From Hell's existing music and may be having them do some custom tracks as well? Personally I think this music is going to be amazing in The Hobbit pin and could very well be some of the best music ever featured in a pin.
Can you imagine the song playing above with all of the cool light shows and the Smaug toy talking to you during a multiball mode?!