hexameron wrote:I was surprised to learn that Apple release any Source at all, but if someone had a lot of time on their hands it might be worth looking at. Since I know nothing about Apple I will shut up now.
Apple doesn't release source code. The open source portions of OSX are built upon the modified BSD project called "Darwin". Darwin serves as the core of OSX, but the similarities to a proper posix environment end as soon as the GUI is enabled.
http://en.wikipedia.org/wiki/Darwin_(operating_system)
Large portions of free software on OSX can be installed using Fink or Macports, but they utilize the Xserver which is slow and clunky and uses additional RAM and CPU on top of the proprietary Aqua GUI.
As far as porting OSX to the Pi, it's simply not possible. The open source portions could technically be, but the rest of the OS that is comprised of proprietary code could not. Not without internal development by Apple, and since I don't think Apple is interested in make ANYTHING that only costs $35 that is simply not going to happen.