I'm probably in the minority, but I would vote against markdown support. There are tons of minimalist markdown editors out there (have a look in the Mac app store for starters). At least make it switch-offable.
I'd vote against list automation too, because it changes the way the cursor and keyboard behave.
URL detection would be nice though, since it only affects the visual display and mouse behavior.
I'd also vote for a constant-width font option. Preferably Consolas or one of its knock-offs.
It would be nice if the line number, column number, and number of characters in the buffer were reported in one of the corners.
Interesting, thanks for the feedback. I definitely plan on adding an off switch for Markdown, and will only be going through implementation if it doesn't impact speed/usability in a noticeable way. The plan is to make it a minimal implementation (i.e. keyboard shortcuts only) and barely something you would notice you had.
The reason I'd like to add it is because having switched over from TextEdit and Evernote, the one thing I miss are the Cmd+B,I,Us etc.
Have you thought about a subtle markdown support like a syntax highlighter? Vim does this for example. Bold things get displayed bold with there stars, headings get bold and colored (red in my case). It allows to read the markdown source and have the effect of formatting at the same time.
