Art's too subjective to be 'classified' these days. I could shit on the floor & call it art, hell I could put it in an exhibition and people would pay to see it.
Me & my floor shit would be famous.
Tracey Emin's a fine example of such things
A bed with authentic jizz stains etc, and it is classed as art.
http://en.wikipedia.org/wiki/My_Bed <-- for ref