I really enjoy graffiti murals, and I go out of my way to photograph them in my own city and when I travel. I will see them when I driving or walking around and stop to look for a moment and try to understand the perspective and message of the artist and take a picture if I can.

That said, I don't much like tagging, tagging is generally not art in my opinion even if you can say artist styles are used within it. Tagging is all about ego and selfishness, it's there purely for the sake of saying "I was here", as if you are the most important person in the city that you should claim to put your name on that wall.

I've met quite a few graffiti artists all over the world in my travels, and the people who tag and the people who paint murals are by and large /not/ the same people. The folks who paint murals are trying to say something, the folks who tag have nothing more to say than to try to create a monument of some kind to themselves. I don't respect taggers, I do respect muralists.