Oh man, that is SO HOT!
In his screenshot in the first post he only gets ~50 frames per second, but on my MacBook Pro (which is admittedly dual-core) I'm getting at least 170 fps and it often goes as high as 250!
The A* pathing looks like it handles the non-grid situation pretty well, too.
(I just love WebStart for demos like that. Can't get any easier to try out a demo. )