My Mac mini finally arrived last Thursday. What were the first things I did with it? Enable incoming ssh, install the development tools, and modify the code needed to get the Vesta repository mounting on Darwin. This only required minor changes over the FreeBSD version I wrote earlier. It's getting easier with each new OS.
Unfortunately, as I've long pledged to port to Solaris first, I may not make a lot of progress on the MacOS X port for a while.