A nice feature would be to be able to swap the planes so that you have the option to write on the right and have the formatted output on the left.

Mou, the great markdown editor on OS X, is also set up as this web app, with the formatted output on the right and the input area on the left, without an option to switch it.

Am I weird for wanting to type on the right? Is this some odd "handedness" issue? (I'm right handed)