What is the difference between "Reply" and "Quick Reply"?

[Gregory]

If you go to Settings >> My Preferences >> Display there is a checkbox at the bottom to enable "Quick Reply". I enabled it, and sure enough there is a new button next to posts so that I can quick reply, but I am not sure how it is different than a normal reply.

[LiliMcDonald]

Quick Reply is supposed to have a text field pop-up directly on the page so you can type a reply -- no formatting or other options available. This replaces the regular Reply > Full text editor page. However, it appears quick reply is not functioning properly right now. I will report this bug accordingly.

Thanks,