Fun, but buggy.
When the physics work, they work great, but when the ball starts sticking to objects, it gets frustrating.
It was also annoying moving objects and having them jump before you move them. It made it very tough to make minor adjustments.
Everytime I play, everythings fine for a while. Then it'll crash IE or freeze Firefox.
Much though I'm enjoying this (I used to love Privateer) I'm going to have to wait until it's more stable.