Superb. It would be even better if you could give selection of the style. I mean Say instead of rectangle u can give option in ACP for round or star (if possible)..
Anything is possible - you might want to try styling it (look at unread_post_count.css) - specifically you could play with border-radius to make the corners round :) Thanks for your review.
Just installed this add-on on my forum after converting to XF. I like this add-on a lot, I had to edited the theme to fit the colors of the post count. But it's worth it.