Ok, then here's the bug..
I add an RSS feed for a Wiki. When I first enter the feed, there's a list. I select a sub-article category and it shows me the first article in the list. In portrait, there's no 'Articles' button in the upper left. Once I rotate the screen to landscape, then back to portrait, the button appears. Until I rotate, there is no 'Articles' button. So, you are kind of trapped there. If you don't think about rotating the screen, you would be trapped in that article with no way out.
Of course, I didn't think to rotate the iPad as I had it docked in the Apple iPad dock. So, I didn't grab it and attempt to rotate it.
Anyway, you probably want to ensure the 'Articles' button always appears at the upper left of each article whether or not the iPad has been rotated to landscape.
I've attached two images: One before rotation, one after. You'll see the button is missing on the 'before'.
Thanks.