Graffiti: is it art or vandalism?

   In Toronto people are questioning the spray painted work on the grounds and walls of buildings all around their city. "Even if your Picasso, you’re not allowed to paint on other people’s walls,” said Elyse Parker, a city official who is heading Toronto’s crackdown on graffiti.
  But lately some people have been opening their eyes to these acts of urban design. although others still continue to say that its "Graffiti" and "vandalism" and that they despise it.
  i belive Graffiti art is a form of self-expression. It’s another way artists can show their talent and opinions to the public. It’s the ones who run around town with a thick marker, scribbling their “crew name” on anything they see who give graffiti artists’ a bad reputation.
  Every new wave of art starts somewhere. Our generation’s art just happens to start on a wall.
  what do you think? is it art or vandalism?

here are some examples:

 

sources: (http://www.theartnewspaper.com/articles/Graffiti:-is-it-art-or-vandalism?/28040 )