i think it depends on how good the graffiti is, cause ive seen some awesome stuff around but ive seen alot of the "tags" by 14 year olds pretending to be big which are just shite. Chuck Close has done some really good pictures with a spray gun( does that count as graffiti?)
it depends... if it were some douschebag spraypainting "fuck" across the side of a house in some fancy lettering the yes, it is most definatly vandalism. on the other hand, an illegal bilboard depicting a well painted eight-year-old going off to war is a work of art my favorite example being Ron English http://www.popaganda.com/
I went to paris about 2 years ago this spring but i saw some major graffite and it was the shit most of it was artistic, and not just stupid words, although i did see some french words. All of the uderpasses there looked soo cool Definitly go check it out