I actually really liked the natural atmosphere here. The tones and the light is just perfect. It's really nice to see the focused expression on the old guy's face. And the guy behind has noticed your camera I guess.
The timing is also really great there. Because when people notice the camera they usually feel uncomfortable, but here everything is in the natural order.
The focus is nice enough to keep the vision nice and clear, and also it's supporting the main theme of the photograph.
This photo inspires me to go out and take street photographs. It's really well captioned and a nice photo which reflects the normal day life.

I enjoy the atmosphere and the impact this photo has from the first glimpse. The main protagonist, the man reading is strong but yet his surroundings are sufficiently alive and as focused as they should,to support the main theme. The tones are well refined and do not mix with each other in order to create an ambient (cannot describe it else) and non focused picture. Tones, shapes and cropping are excellent. The timing is a also an element which supports the photo. The people in the background looking towards the photographer depict the curiousness and interest of the everyday people seeing someone taking pictures in the middle of the street.(haha greek slung). But what makes it a great photo for me is that it inspires me to continue shooting from time to time.
From the other hand this is just the opinion of a graphic designer and not a professional photographer.
Hope it helped.