Apparently I'm not the only one who found that iMessage no longer works in iOS7. Upgrading to 7.02 didn't help either. You did know 7.02 is out right? I suspect an update with a more classic look which also fixes all the glitches mentioned in this article
will be out before too long. As far as battery life issues I mentioned some fixes in my last article
that can help quite a bit but there's no getting around the fact this OS is more CPU intensive.