Square Enix's upcoming 3DS game Bravely Default: Flying Fairy has only one save file slot. This detail comes from game producer Tomoya Asano, who let loose this detail on the game's official Twitter feed. According to this Tweet, the game has some wireless feature that that makes having only a single file necessary. Andriasang says that Asano did not elaborate beyond this.
This same Twitter feed revealed a bit more on the game. Here are some of the highlights:
I'm very excited about this game. Hopefully the single save file thing won't be an issue.