Apple has made Darwin open source. That, WebKit, and LLVM are pretty core technologies. A good portion of their technology is open. So, it's not just using free software and not giving back.
Darwin is open source but is there anyone here who has actually used it or got a bootable usable machine from it? I mean, can you even run X on it successfully? I never could (didn't try very hard mind you).
The release of Darwin isn't a massive thing I don't think.
There have been several independent ones because they all fail. I don't fully understand the dynamics here, but the inability of the community to create a usefully working OS out of all that open code for over a decade speaks volumes.
I wonder if it is because it never gained enough intertia when Macs are good enough with the Mach kernel etc.? I wonder why the varieties of Darwin didn't catch on?
I think a free software operating system binary-compatible with OSX drivers and source-compatible with OSX applications (through GNUStep) would be an exceedingly compelling product. Which is why people keep trying to make it happen. I don't think it helps that you need XCode to compile a lot of the source that Apple releases, which means you need a Mac.