I have asked that question my self. On the webinar it sounded like it would be left up to each course but it was unclear, that is why I asked for clarification but have not received a answer.
The new rule says as long as you are not playing music for entertainment value and not to gain a competitive advantage it is OK.
I personally like listening to music when I play but I am courteous to the people I am playing with and if they are not OK with it, I do not play it.
And just to reiterate, defiantly no RAP!