I like your app. You're going to get some criticism for it looking a lot like iawriter, but I think that's ok. A lot of people want a minimal note taking app that has some modicum of sophistication (e.g searching notes).

Idea: Can we hide, or collapse the left side bar? That way we'll be able to have a narrow window off to the right/left edges of the screen, much like the notification pane in Mountain Lion.