My only response, after seeing so much discussion of this seemingly unresolvable issue, is regarding Rap. To me, music at least consists of a succession of organized tones. I refer to this exerpt from Webster:

"The science and the art of tones, or musical sounds, i. e., sounds of higher or lower pitch, begotten of uniform and synchronous vibrations, as of a string at various degrees of tension; the science of harmonical tones which treats of the principles of harmony, or the properties, dependences, and relations of tones to each other; the art of combining tones in a manner to please the ear."

Where, in Rap, do we find tones? Generally, Rap consists of rhythmic word play, with tones either non-existent or barely represented. I could live with the idea of Rap as a sort of "folk art" or "performance art," but I cannot accept it as a musical form.