Like this a lot too.

> Earnest shows you the number of words in your text, useful for people who need to hit a particular word-count, but it only re-calculates the number every minute to deter you from constantly keeping an eye on your progress. The word-count should not be a distraction from your writing.

I would maybe have the counter be real-time, but require the user to leave the keyboard (or some other significant action) to show it? (ex: on mouseover). I was trying this out and still was looking at the "0 words" and thinking "damn, I wonder how many words there are."