I think it's the sandboxing that makes the story
The story is quite clear, as you point out, that ASLR and full disk encryption are areas in which OS X has now caught up with Windows and Linux (or Ubuntu as it seems to call it). It then suggests that sand boxing processes and designing the applications (and daemons) that come with the system to isolate different logical parts into different processes within different sandboxes constituted a step in advance of any of the competing operating systems. So that's the leapfrog jump — the fact that the supplied browser, email app, PDF viewer, etc are all now aggressively using sand boxing, for which there is now high level API support.
Whether or not that's a valid assessment is one thing; just repeating what the article already says about areas where Apple have played catch up is quite another.
Re: pre-emptive multitasking, citing Apple's failure to transition to a modern OS until around 2000 feels a bit disingenuous as a comment on the OS they transitioned to.
Re: 64bit, that's been a feature since 2005. The difference in approaches has been that Apple have uncharacteristically gone for a gradual transition, though I think that's because the hardware has made a gradual transition.