I've found that [Pandoc](http://johnmacfarlane.net/pandoc/) has picked up the Markdown torch. It's got the most-needed additions using the probably least-controversial markup additions. Works great, is fast, well-documented, and is actively-maintained.
Eh, again, scratching an itch. He could have done more, but that wasn't his main goal. He doesn't make money off Markdown or anything, so his only real concern with it is how it serves his needs. My point was just that developing software, even popular software, isn't entirely foreign to him.