I find I'm always scrolling to the top of a submission to see who the original poster is. It would be useful to bold (or italicize?) the original poster's username in the comments. This would be simple to implement, and give a bit more clarity to the comment digressions.
I thought of this same feature yesterday and briefly considered submitting it to Ask HN. I decided against as I expected PG's response to be along the lines of "Why, less is more etc. etc." or "Why should the submitters comments be weighed more than others?"<p>Glad to see the positive response. I highly enjoy blogs and to a lesser extent Reddit where the authors comments are highlighted amongst the chatter of regular users.