As I'm writing a small markdown renderer, I find it difficult to even find a name for it, let alone get people to use it once it's ready. So I guess the ol' Markdown is too standard for a "plain markdown" editor to stand out today. Only tools that are polished and dare-I-say full of features beyond normal markdown can stand out from normal Markdown editors to make it into the front page of HN. Sort of natural selection I guess.