It's a little chaotic, and yet I can't look away. I keep bouncing from blurred person to blurred person trying to determine what they are doing. And I ended up wondering whether it was about shadowed patterns on his back or the patterns of the people walking.
Didn't like this on first glance then it grew on me, very quickly and lots ... there is so much to look at - youv'e brought the colours out wonderfully and the title brings one to look at, as you say, the patterns in everything in the picture.
BUSTED!! That guy in the blue shirt knows exactly what you're doing. I always love the play of shadow and light. This would be cool in BW too although I love the colors.