Published on February 22, 2010.
TweetNote: If you think that I missed a really nice disctration-less text editor, or that one of my comment is groundless, feel free to drop me an email.
Competitors:
Ommwriter is developed because of an internal need at Herraiz Soto & Co, a digital creative agency.
I like to call it the "Zen" editor, because of its default background images and ambiance musics: they all bring the belief of zen out by subtle, "quiet" images and sounds.
It runs fast: instant launch, easy switch between applications (for a dictionary search for example).

It really takes it promise of being a distraction-less text editor.

The full interface is clean that's true. Buttons are explicits, the scrollbar is thin but really efficient. Nice.
I put it there only because I know it exists and because a really nice French guy works on it.
Here is the (huge) problem: it is such a pain to install Pyroom on OS X that all urge to use it leaves me instantaneously.
WriteRoom is a $25 software created by Hog Bay Software. It seems that is name is like a reference in the world of distraction free text editors on OS X.

I do not really like to pay software, except if they are so nice that I can't do without. Fortunately, I received WriteRoom in my MacHeist bundle a few months ago.
WriteRoom is really customizable: this is a great point for it. You can indeed set everything from the fullscreen colors to the auto-save frequency.

In addition, it can create two types of documents: plain text and rich text, which can be a really useful feature for people who need text formatting without markup syntax (such as Markdown, I highly recommend it). For example, using the rich text mode allows you to set color, font weight and many other attributes such as text alignment of your text. WriteRoom produces RTF compliant files so they are editable by any other RTF editor.

I don't use this function because of two things. The first is that I have an heavy use of Markdown. The second is that I think this feature is out of distraction-less text editing.
One more thing I do not really like is that you need to move your mouse cursor to the bottom left corner of the screen to display informations on your document (file name, words and lines numbers). I prefer the behavior of Ommwriter: you just move your mouse (it is equivalent for me to a light gentle touch on my trackpad) and those informations appears.
To be frank: I hate it. Firstly, it is made with Java. It is not that I dislike Java, but it leads to problems: slow performances (it is long to start, not really swinging) and bad system integration (does not totally hide when I press +tab, keeps other applications from taking focus...) mainly.

Furthermore it doesn't deal nice with UTF-8. For example, I opened and saved my document in JDarkroom, without modifications. Here is the result back in Ommwriter:

(Trust me, I don't let my 2400 bauds modem write my documents)
To conclude, I have a preference for Ommwriter because of the real simplicity of its look & feel. I also enjoy its ambiance songs! :)
Note: for each editor, I used it to write the corresponding paragraph.