Re: Whats the deal with open source?
I suggest you read up on the subject a bit more, not that I'm an expert, but your questions are easily answer with a bit of research.
GPL is a licence agreement, not a company or entity capable of suing anyone.
When software is licensed under the GPL, any changes made, and crucially are then distributed in binary form, must make the changes available under the GPL again, but not necessarily via source code drops. In this instance, the linux kernel is used, and Google (or motorola) could respond to requests the changes made the linux kernel. As for code that Google has written, it's their copyright. They can do what they like with that.
Finally, OS X isn't based on any part of linux. However it does redistribute quite a lot of open source components, many licence under GPL, and many patched to work on OS X. In compliance with the license, you can find those packages at http://opensource.apple.com - heck even some there don't require your changes to be published, but they do anyway. Shocker!