"Different from something like VII, which we expanded upon afterwards, with Fabula Nova Crystallis FFXIII, we've thought about an expansive world setting from the start," said Hashimoto in an interview with Nintendo Dream translated by IGN. "Under the idea of wanting everyone to be sucked into the world for 10 years, we're preparing a number of categories."
Hashimoto also classified four groups of developers working on four distinct aspects of the Final Fantasy series: the Nova Crystallis group, the Ivalice Alliance (Final Fantasy Tactics, Revenant Wings), the Crystal Chronicles group (that works "exclusively on Nintendo hardware," according to Nintendo Dream) and the MMO-centric Final Fantasy XI group.
Does this mean we'll be waiting until at least 2017 for Final Fantasy XIV? It's unclear, but regardless, we'll have to play nicely with XIII's characters for many years to come.