I remember at the end of Animal Planet's G-doc. Steve Ryfle's response to GFW being the final Godzilla flick was a chuckle and "There are plenty of reasons, plenty of
green reasons for Toho to make many more Godzilla films."
So the last few didn't do so hot, but the Millenium series must have made some dough for Toho if they decided to double the number of films they were gonna make in the series from 3 to 6. Godzilla films don't cost as much to make as your American blockbuster. His films don't have to be number one for several weeks to be a "success." Godzilla is like Bugs Bunny, Doctor Who and Star Trek; there is no way for us to be rid of him.
... but what I would really like is a new Rodan movie!
The whole "jumping ship" thing is silly. I've been a Godzilla fan all my life and a decade or so of no new movies isn't going to do anything to me.