I'm a little confused about the handling of text messages. If I receive a new text message in an open thread before the screen turns off (after I sent my reply), I have to hit the "Message (1)" back button to go back and read the reply to what I sent. In iMessages, the threads autoupdate in realtime so there's no hitting back. Why doesn't SMS on the iPhone appear to allow threads to update in realtime when the screen is still on as the reply comes back?