Um, streetlights don't move, but cameras do. As stated above, it was a 2-second exposure. Press the shutter button, shutter opens and flash fires, and as he pulls the camera down, the shutter is still open. The foggy colors in the background are motion-blurred items lit by the street light. No motion blur close, as the close area was very dark; just the flash exposure, as was intended. Also, the flash exposure was low because of the street sign reflection fooling the metering.