When viewing a story on iOS (full site) and hitting the back button to get back to the list view a much older, previously viewed, index is shown.
I'm not sure if this has to do with caching headers or what.
This happens to me too. Safari, iOS 5.0.1, iPad 2.
I can confirm this. The problem is that the referrer URL has &count=N but N is wrong (it's usually the next 25 from the link that was clicked). It's super annoying.