Okay, I admit, this is a tenuous claim. However, I noticed in the contacts and phone app that when browsing through your contacts, the search field is now permanent - this reduces space in the actual contacts viewfinder and thus why it isn't permanent usually. BUT if there was a new taller 4" screen, there would be no need for the search field to be concealed at the top because of the increase in screen size? No obviously this has - by accident - made its way through to the UI in iOS 6 and in my opinion looks horrible on this 3.5" screen as the scrubbing letters on the right are all condensed and it looks a bit cluttered. But this wouldn't look bad on a 4" taller screen and would also be more practical: so maybe a sign of things to come?