Nice graf pick. I have one in my portfolio. I am currently working on a graffiti portfolio. Shooting other peoples work, and sometimes mine. Congrats on a top 25 photo!
tough decision on the vote.. your photo, while it has a sign in the middle of it, is really nothing more than a photo of someone elses art work. However, having a sign in it does mean it meets the challenge and the sign is not someone else's work... so we have quite a conundrum where a vote is concerned.... (pause) ok after a brief pause I find myself drawn to the striking images painted by the other artist(s), not the sign, which should be the main subject... I feel since in my own humble opinion, the grafitti has too strong of a presense not to be concidered the main subject, and therefore is really a severe over use of someone elses work.. it's like you took a picture of someone elses picture.. for me, that doesn't work in this type of challenge... on a technical level, your color, focus, and lighting is great!
Beautiful colors and variety - I really like the centered composition with the sign smack in the middle because it brings order to the chaotic colors and shapes. You get a 10 from me.