Ooh, that's not true, I've crashed OSX a fair number of times. Why, just 2 days ago the keyboard on my MB randomly stopped working. I couldn't type a thing (until rebooting). Both my MB and MBP will occasionally have the mouse not show up when waking the machine up (have to reboot), and sometimes freeze when I zoom out to all windows. On my mac pro desktop, I've had the disk utility freeze the entire OS just by running it (without even doing anything), happened at least 3 or 4 times last week.
Oh and my (older) MBP freezes 25% of the time just by plugging something into the dvi port. It's nice when you're just starting a presentation and have to say: "sorry everyone, just let me reboot". That MBP also has issues "waking up", it likes to stay asleep (lazy).
And let's not even get into the shitty batteries and how the MBP will randomly blank out (turn off) with like 20-30% battery life left. No warning, nothing, just powers off.