[steveneo]

TextNut markup is nearly same with common markdown and you can switch between them. The existed text is also automatically converted. Actually, only 2 major differences. One is ~emphasis~ as emphasis. Another is header uses textile format, i.e., h1. h2. ... format.

[Terretta]

"Nearly the same" means translation is required.

Also, the point of Markdown is to look formatted as plaintext. The atx headers or == headers accomplish that. I like textile, but its headers don't accomplish the same goal.