OSX itself is built on Unix. So they definitely leveraged a lot of technology and innovation from the Open Source community and have they really given much back? You could almost say they're worse than Microsoft in that regard because at least Microsoft is consistently proprietary! The nice thing about Microsoft as well is that you don't really NEED to trust them, since you can hack everything up anyway. A lot of Mac applications haven't been hacked yet, so you really do need to trust Apple. Will they take care of you in the long run, or will they let people take care of you?
The most notable example I can look at is with content streaming to the Xbox 360. I have a lot of content in my computer, a Windows XP machine. To stream content to my 360 from XP I have about 5 options available to me, most of them free. Even Linux has a couple of free options. However, on the Mac from what I know, there's only 1 option and it costs money. Of course you COULD go with an Apple device, like the Apple TV but you start getting into the all Apple world. Which is fine if you're a Mac fanboy like a couple of my friends. Personally, I like using the best device in each particular niche, and Apple isn't that for everything, therefore the ability to mix and match is very important to me. So far, Apple hasn't been very good with that. For now, I'm staying away from owning Apple products, but I like using them, and I look to my friends with a little bit of envy.
The awesomeness of the Eee hit home this weekend when I geeked around with it and ended up messing up some programs. After searching around on the web a bit I discovered that it has a built-in "restore to factory defaults" functionality that is stupid-easy to trigger. Which is great, because I can do whatever the heck I want to the Eee (from a software perspective) and I'll always be able to restore it to a working state in about 2 minutes. I don't need to spend a day reinstalling the operating system and applications. That's so friggin sweet.