Aren't you just thinking about episode 14, when the episode ended with a joke about how there was no way Gentaro would ever fall in love? That's clearly supposed to foreshadow Nadeshiko, but I don't think there was any reference to her afterwards.
there is no other reference afterward. The dialogue supposed to go like this (not exactly, but close enough)...
Gentaro: One day I will be fall in love!
(Someone I can't remember): With who? Someone from space? That's impossible...:laugh:
Ryusei and real-Nadeshiko also go to the same school.
now that you said it, I realized that Nadeshiko did wear the same uniform...
so...what happened here is that both W and Fourze is in the same world, but OOO here is the movie OOO with the same ending as the series one?