My first reaction was envy, after having seen Perl geeks with iBooks or PowerBooks at recent YAPC::Europes... but then I saw a couple of things which didn't quite fit. First, the task bar at the bottom (or is it called "dock" in OS X?) wasn't wide enough, and second, there was a display showing space free on "C:" and "E:", which seemed unlikely... then I read the post.
Looks pretty well done, by the little I've seen of Aqua so far, but it did confuse me quit a bit at first!
(As someone else pointed out, "that's wrong!")