Basically what others have said - steady cam, foam over the mic, and maybe a little less time focusing on the close object in those shots and possibly moving the focus to the rider during the shot.
I like the video. Is all that shot from a SLR? I like the close-up shots especially the water. I would have like to see some of the jumps shot from different angles. It's hard to see how big some of them really are. That song is sick. I wouldn't play the whole song ethier. Acid Raindrops- People under the stairs is a dope song also. That is a great video, Keep up the good work.