How to hide it? It is way too yellow, and automatically switched on when activating whizzytex. I looked at the Emacs variables but cannot find it there. Using Ubuntu 13.04 and Emacs 24.
Look for customize-group (M-x customize-group RET). The group will be called WhizzyTeX. There you will find "Whizzy Point Face". Untick the background-color box, set for current session and save for future sessions.