The film's writer I. Marlene King has since gone on to create and produce "Pretty Little Liars" on ABC Family, a guilty-pleasure teen mystery/thriller about a clique of girls harboring secrets and trying to discover what led to the disppearance of their former friend. "Pretty Little Liars" is currently in its third season, and the success of the show (it's ABC Family's top-rated series) has King looking to develop "Now and Then" into a drama for the network as well.
According to Variety, this project is still in the early stages and "likely wouldn't reach pilot stage until next year." Since the show would presumably cut between the characters as tweens and their lives as adults in the same fashion as the movie, it would solve the problem some other shows on the network -- like the very enjoyable "Bunheads" -- have faced in terms of balancing storylines to appeal to young audiences but also potentially reach beyond them.
Here's mini Ricci romancing mini Devon Sawa in the film: