I just recently got an iBook, and I while I really enjoy it, the whole gaming disparity vs. PC's is a big downer. That being said, Shippy1984 on the mac is a big step in the right direction. It is much more fun, especially right off the bat, than that stupid nanosaur game apple packages on new machines.
As Mason Bond says in another review, this game is definitely fun for the nostalgia factor. Some people might give the game a bad graphics rating, but considering that it apparently is meant to epitomize the genre of the 80's arcade shooter, I'd say they're dead on.
I was pleased to note that the sound and usb gamepad compatibility work without any changes, either.