When the last unread item is viewed, both buttons at the bottom say Done. This is confusing and unecessary. It might be better to replace the Previous and Next buttons with a gesture, or with smaller buttons.
This I disagree with. It only says Done/Done if there is were no previous read stories and no stories to go to. It's a confirmation that you haven't done anything in that site except read a single story. I call it a quirk. Not only a quirk, but one that I actually like. I use the iPhone app quite often now, and that never bothers me except on an aesthetic level. I think that by making the Done buttons slightly different colors, I'm making it easier to hone in on the conceptual model that users have built in their minds as to what's happening on this story detail page right now. And with two Done buttons, it means there's nowhere to go and you've been nowhere else, so time to return home unless you're looking for a specific story you've already read.