there will be 3 FFXiii's,
Final Fantasy Xiii-
Final Fantasy XIII has been described by the developers as the 'light'
to Final Fantasy Versus XIII's 'shadow', though it has been
specifically stated that the two games do not take place in the same
world or society, even though both stories share the same creation
mythology based around the Crystals.
Final Fantasy versus Xiii-
According to interviews with the developers, the world of Final Fantasy
Versus XIII that exists within the last city to control the Crystal, as
well as it's culture, is directly equatable to ours. The world outside
the city, on the other hand, is much more medieval, and outsiders wage
an ongoing war against the city and its residents. Their goal? To take
control of the Crystals, and thus control magic.
those two games are for ps3-
and Final Fantasy Agito XIII.
Final Fantasy Agito XIII is an online RPG in development for mobile
phones, and is being developed by the same team as Before Crisis and
Crisis Core. The title, "Agito" is Latin for 'to put in motion'.
Players will be able to choose one of twelve characters. The
characters are students at a the Periticium school of magic, and in the
game, players will control the daily life of their character and
interact with fellow students.