As a notorious Markdown critic, I have to say, their syntax really looks like a decent attempt of support for technical and scientific documents. Having used reStructuredText for a thesis with a lot of bells and whistles, and having used org-mode mostly ever since, I am not just admitting it willy-nilly. Then of course some of its syntax and syntax concepts are straight out of reStructuredText's book, so it makes sense, that it would inherit the capabilities as well.

What I haven't seen at a quick glance is the ability to link to any place in the document (sink) from withing the document itself (source). Maybe I did not look far enough in the examples. reStructuredTex can do this, and org-mode can do that too. And I don't mean just linking to existing headings. The other required things like footnotes and citations and so on seem to be there. Now if this reaches mainstream and we start writing documentation in it, there is great potential to have finally good documentation, not limited by the likes of github markdown. Of course same is true for reStructuredText and org-mode. From that perspective, one could ask, why yet another format was necessary, rather than improving tooling for lets say reStructuredText.