I don't undertand bamccaig comments.
I mean, it is a big "music box". The spigots move levers that release the marbles that fall and hits the xylophone, percusion and bass gitar strings that produce sounds, then marbles are gathered and returned to the hoopers by the conveyor belt and it starts again.
Of course it is edited. Any video should be edited, specially those that aims to do some artistical stuff. And anybody who has done* any serious video recording knows what happens if you don't record sound correctly.
And of course the video was created to gather visits. That's why YouTube was invented for.
[This message was edited a lot trying to explain it better, English isn't my first language there * should be some errors]