WHAAAAT!!

http://www.dummies.com/how-to/content/understanding-buoyancy-using-archimedess-principle.html

The ball has air in it. The jumper used the artificial force of his weight to carry the ball well past it's buoyancy point. Since every action has an equal and opposite reaction, the ball skyrockets.

Drop impact is different.

I think it may be a combination of the two. I don't think if you just held the ball underwater a few feet it would launch that high when letting it go.
https://www.reddit.com/r/Physics/comments/41fpzm/water_shoots_ball_into_air/

I decided to ask in a science forum. Hopefully i can get some serious sciency explanation

Also made me think of this although dont know if it applies at all http://videosift.com/video/Stacked-Ball-Drop

Possibly, but I can't think the small amount of displacement would launch it that far. Also, it would take perfect timing, like under a second.

*happy, *kids

Adding video to channels (Happy, Kids) - requested by Zawash.

You've almost certainly got it with that. Displacement is enough to give the ball initial inertia in the right direction, then the "Rayleigh jet" or "Worthington jet" boosts it. It's perfect timing combined with a near perfect cannonball.
Think of the speed a splash goes skyward. If you accelerate something with more mass, especially something aerodynamic like a mini football to the same speed, it's going to shoot up like a rocket...which is what happened here.

Misleading title is misleading? I see no instructions on how to rock.