I think as an engineer the type of things one might get to work on at Apple could be more interesting than the type of things one would get to work on at a bunch of the companies you just listed. At Apple there's everything from OS to compiler to drivers to UI to hardware, etc.

I don't want to work there, as I know people who have and it sucked, but, I can see the appeal for some. Also one person I know who did a stint there got some rather obscenely large amounts of cash.