this is very good summary of what's out there.

the categories seem to be a bit mixed up, but i don't see very much stuff that is missing -- considering the difficulty of being exhaustive -- except for three large and notable exceptions.

the first one is "multimarkdown composer", which is found at http://multimarkdown.com.

next, "strapdown", at http://strapdownjs.com.

finally, "marky", at http://markdownrules.com.

-bowerbird