mcsancherson
he played O Canada

GravidWithHate
It happened in Montreal, at their annual "Just for Laughs" comedy festival. The clip is probably taken from the CBC broadcast.

You owe me $100.

oogaBooga
Uh yeah. This is real. Sorry to burst your bubble.

Just because you cant do something doesn't mean someone else doesnt totally kick your ass at it.

oogaBooga
whoops that was for professor chaos

fluffy
I totally believe that's just crappy video encoding to blame there.

fatatty
I actually looked around and found someone who noticed a giveaway at 1:34 in the video. Right after that he plays one note twice, but the balls land in two different spots on the keyboard.

That probably means the keyboard just plays the right note when a ball hits it. So he is juggling off the piano in the correct rhythm, meaning the piano wouldn't have played faster than his hands, but he doesn't actually have to hit all the right keys.

So half-fake but still impressive.