The play tests are going well. More than a dozen people have played the game so far, ranging from non-gamers to fellow developers. I've had an extremely enthusiastic response from local multiplayer games, as well as a great reaction from those playing the single player tournament mode. Almost everyone who picked up the game, wanted to play until they beat the single player tournament. The difficulty level seems about right, and I've had some important bug reports.
Although the game is fairly easy to pick up and play, its become clear that it would benefit from a tutorial level, so I spent the past few days building one. I've got a couple more touches to do on it, and then I will expand the focus tests further while I return to bug fixing.