One major issue that was pointed out is the fact that the legs snap. The leg swinging forward is too far and causes the knees to pop. Two ways to fix it are to lengthen the stride or to not have the leg swing so high.
The arms are not bent towards the body enough on the upswings.
The head moves side to side too much and not enough up and down.
The wrists have good overlap and followthrough and he has an upbeat step.