Why should I try scrolling everywhere all the time instead of having the UI indicate to me that there is more content? Especially if it isn't clear by having a word or sentence cut of. Maybe the scroll area ends with a paragraph and it's not clear there is more. Why put aesthetics over usability?
Some other comments here claim iPhone users develop some kind of swipe tic where they instinctively try to scroll around on every screen that opens. Would be a pretty sad testimony to this UI concept.
