When typing on the iPhone 5 in safari the editor jiggles. Actually doing it right now. The text I'm seeing while typing is jiggling going up and down. Each key stroke the screen goes down slightly on the 6th keystroke the screen jumps back up and the cycle continues.
It was fine for a while, but it came back. This behavior is inconsistent. Writing this reply is OK, but when I've started my thread to report a bug, it happened again.