In a literal sense anything making noise can be considered music to the right listener.
I however feel that as the high end of human achievement has progressed, I think in an artistic sense certain things should no longer be considered music in anything but a technical sense.
In general I do not consider a bunch of primitive tribesmen making ear-raping noise by banging sticks and rocks together and such while howling to be "music". I think the progressiion of society has gotten to the point where something that primitive on it's own can no longer be considered music, except perhaps to it's performers, and typically they are only doing it either for the sake of cultural preservation (though to some extent you have to ask why someone would preserve that), or because they haven't been introduced to anything better that they could have/do practically.
Yes that is an elitist way of viewing things, but they are my thoughts.
Understand, I worked on two differant Indian reservations. Due to various festivals and such they have had displaced "indiginous peoples" from all over the world show up to play music and such. This has included native American tribes, but also aboriginals, african tribesman, and other similar groups. With rare exception, a lot of the performances wind up being of the sort that can almost cause physical pain to the listener.
Now, before someone says "I've heard Native American music, your nuts", I will tell you that you probably haven't, not really. See one of the contreversial things in Indian politics nowadays is about how they send the tribal members who are going to put on shows to special "Indian Schools" to learn how to dance, sing, tell stories, and similar things. They blend together the best elements of all the tribes, change it around quite a bit in order to sound as positive and poliically correct as possible, and present that as the face of Native America. To some tribes this is offensive, because it's not authentic, it's a political move.
To put things into perspective when I worked for the Mohegans, for a while they were (briefly) boycotting shows for this reason, but eventually broke down. The image Native Americans put forward of being nomadic, "one with nature" sorts who had no idea of property rights and were victimized and such is a political one. The Mohegans on the other hand were a settled people, they lived in villages made of long houses, while their techniques were not as refined as overseas they farmed, and they very much did understand the concept of property ownership, farmland, and similar things. The tribes on the east coast were substantially differant from the ones in the midwest, south, or west coast, so why should they dance like them, sing in a combined style, or tell stories that have absolutly nothing to do with their actual mythology. Ask your typical "well informed" American about Indian mythology and they will probably tell you about animal spirits, an earth spirit in all things, and stuff like that. Very few of them that have not visited the tribes down here in person are liable to have heard of Granny Squanit and the little people, her husband Mou'shup the Giant and others. Indeed storms were supposed to be when the two of them had their occasional fights.
I'm rambling and way off subject, the bottom line is that actual experience has convinced me that "primitive music" (the real stuff) is a contridiction in terms.
Also for those who have read this far, I do not think a lot of "rap" is music. To be honest a lot of it just seems to be people talking over a beat, rhyming isn't even a part of it a lot of the time, and if there is meter involved at all it frequently eludes me. Some "rap music" I've listened to has consisted of nothing but some rapper(s) talking about other groups of rappers and how they aren't "for real" or whatever else.
Or simply there is such a thing as rap music, but I think an increasing portion of it doesn't seem to be musical in the least. Nothing to do with the content, it just isn't.
Maybe it's a phase, but when I consider "Eminem" one of the few people in that style that is actually a musician (and I'm not a fan) and he seems to be hated by a lot of the community for that music, I find that a little disturbing.