Actually, I predict that FF Versus XIII will take the same or LESS space than FFXIII.
What really consumes disk space is CGs. And FFVXIII probably will not have a world as or much more bigger than Rage or GTAIV(with fits in a DVD9).
A BD-DL is probably a given, but do not expect a dual blu-ray game. If they need some space, there is a solution called compression.







