I think the best strategic move for Google is to wait. They should allow the Maps issue to continue to tarnish the iPhone 5 launch for another month or two, then release their own Maps app that will capture the marketshare of iPhone power users (the people Apple actually needs who would send in problem reports). This would let the dark cloud remain over the iPhone 5 long enough to tarnish it in most peoples' minds, but not long enough to let Apple to get any substantial data improvements from it.