i think this issue has gone completely polar. though resorts may not ban music players, it really comes down to the responsibility of the rider. if you do have an accident and you are wearing earphones listening to music, be prepared to have that go against you with insurance, legal matters, whatever.
though i don't necessarily think it should be banned, i do think people should be aware of that they are increasing the risk of an accident.
on a side note... people that run on the right side of the road with headphones are really just asking for it