In an interview leaked today from the pages of Japanese gaming magazine, Famitsu, some new details were revealed regarding Square Enix's upcoming title, Lightning Returns: Final Fantasy XIII.
According to the interview, the game will feature a real-time mechanic similar to the one employed in The Legend of Zelda: Majora's Mask. The entire game takes place over the course of thirteen days which progress at a rate of about two hours real-world-time. As such, it's meant to be played multiple times, experimenting with what can happen if you make different choices.
The tidbits also show that the game is only about 30% of the way toward completion, and that the battle system edges fairly close to being an action game, using a form of Active Time Battle.
There's many more details over at Andriasang where the story originally broke.