I just got a new iPhone 5, had a 4s I have the same Mac and everything transferred upon registering new phone except the music library

Howdy nooneusedthisname,

Thats an interesting issue you describe. I would recommend restarting your iPhone and try to sync your music over again.

iPhone, iPad, iPod touch: Turning off and on (restarting) and resetting

http://support.apple.com/kb/ht1430

Restarting your device

1. Press and hold the Sleep/Wake button for a few seconds until the red "slide to power off" slider appears, and then slide the slider.
2. Press and hold the Sleep/Wake button until the Apple logo appears.

If need be I would next recommend doublechecking to see you have Sync checkbox checked in the music tab of iTunes for your device.

Cheers,

Sterling