The problem: blender doesn't warn you at all, when you quit the program, if you have not saved your work. That hurts me, because I am very used to certain keyboard shortcuts, and the Mac version uses Apple-q [CMD-q] to quit.
Rather than try to remember not to use Apple-q (I had no luck with that!), I changed the Mac shortcut to something I'd never use. Because the Mac replaces the Apple-q shortcut with my weird one, the Apple-q shortcut no longer quits blender. Now, only the default blender shortcut, CTRL-q, quits blender.
Surprisingly, that helps me a lot. I can learn not to use CTRL-q until I've saved my work, because I don't use CTRL-q to quit anything else on my Mac but blender.
But I can't seem to change my reflexive habit of doing Apple-q to quit. Now, when I do that in blender, nothing happens... which is lots better than blender quitting and taking the last 2 hours of work with it.
I hope this helps some Mac blender users. The vets say "just get used to the blender way", but my problem was that the Mac shortcut worked, too, and I kept using it. All fixed.
