It isn't currently a problem for me, haven't had any complaints on this score, but there are some png images on the current game release etc. so it is a little worrying.
Also, does anyone know how to make the Microsoft Reader add-in thingy for Word work? I've tried using it to create an e-book and it just doesn't seem to do anything at all. Alternatively, can anyone suggest an alternative to Reader Works, which is fairly expensive in its registered version and a pain to use.