I like a well created Mural by a skilled artist. Some are very good, and some are not. It also depends on the message if any. Each person interprets Graffiti differently.
Here is a little history
http://www.daveyd.com/historyofgraf.html
Here is a well done Mural. This is located on 104 st. and Lexington. I don't know the artist.
In the link here you will find more up close work of the unknown artist above. You will also see of of De La Vega's work too. De La Vega is not one of my favorite artist.
http://www.flickr.com/photos/clarisel/40193065/
Here is a De La Vega
And another one of De La Vega
There is only one De La Vega Mural I like, and I could not find the picture. It's an imitation of a Picasso.
A lot of scribbling like this which to me is real Graffiti, I don't like.
I guess it's up to each one of us to make up our own mind about it.
UK graffiti artist Banksy
I like what Banksy did here. He took a blank wall and made an interesting image.
And
And
Sorry to say, but, I could not find pictures of the real master works of art in our city. You really have to see them up close to appreciate the color, and the skill of the artist.