A couple more details on the still elusive Final Fantasy Versus XIII have been confirmed and expanded apon in this months Famitsu.

The full names of both Noctis and Stella have been confirmed to be "Noctis Lucis Caelum"(meaning Light Night Sky), and Stella Nox Fleuret (meaning Star, darkness, latin). During the trailer shown at TGS, a scene in show in which Noctis and Stella discuss a special ability they both posess. This ability is to be able to "see light". It's not entirely clear what that's meant to mean at the moment, but Noctis tries to keep quite about it as Stella speaks of it openly, even asking how he aquired the ability.

Nomura also re-affirmed that Noctis is not a depressed emo, but hides his shyness by "acting cool". Stella is quiet the opposite, showing strong character as a reflection to her upbringing.

Nomura also mentions that you should "watch Noctis closely", as there will appear to be something different about him that he's hiding, although his friends can see through this.

Source: IGN