Well, I don't have any info, but my gut instinct is that they will use the movies to resolve the rest of the Grand Story Arc hinted at in the "she must be the other" line, in the same way Joss Whedon used
Serenity to resolve the arc he set up in
Firefly.
And I hope and pray, based on the commentary on the last season 4 disc, that they will get Fry and Leela together.
But I hope and pray even more that Leela's "other-ness" is more than just being Fry's helpmate or baby factory. I'd accept something along the lines of the (brace yourself for really obscure reference) the plot gimmick of the movie
Krull, where the completed marriage between the prince and princess gave them the power to defeat the evil alien demon lord whatever thing - the two of them together being stronger than either one alone. Still, I'd be most pleased if Leela had a destiny of her own because of who and what SHE is (rather than just her connection to Fry). Though I want them to end up together just as badly.