Well, Lepus Rex, remember the stereotype of beatniks reciting their poetry to bongo rhythm accompaniment in coffee houses? Remember Allan Ginsberg reciting poetry to the drone of an Indian shruti box? It was even called "beat", but it was still poetry. Then, the urban form of poetry that we call rap came to the awareness of the recording industry, and geez, you couldn't call it poetry, that's too intellectual, too uncool, too hard to sell. It's my opinion that marketing people decided to call it music instead of poetry. Even though it is spoken with musical accompaniment soundtracks, backup singers, etc., speaking is not singing, poetry is poetry, and I'm sorry the recording industry chose to call it music instead of what it is - kids would think poetry is "cool" if they had. But, poetry is egghead, music is cool, so it is called music in order to sell more of it.