I am playing a very simple game of not counting chickens before they hatch--the phrase I wrote above is not the only place Sakurai has mentioned this, and he does not use any quantifying measures in pretty much all of his interview statements on the subject, just that the 3DS version will have stages based on handheld games and that the Wii U version will have stages based on console titles (he has also mentioned music in this regard). So far, the stages shown have not deviated from this (and we've seen roughly twenty between the two versions).
Character repped franchises lacking stages period is also not new to Smash. It could be that Sakurai is taking a completely different approach to how he chooses stages than how he did before.
It's fine to speculate on it, but to flatly state that there "will be" exceptions to the general rule is unsubstantiated at this point.