I'll be honest here.
I think a lot of things are happening around Versus. Probably renaming, which may bring a lot of changes to what was planned for the game.
It is possible that what we were familiar with, the "FF Versus XIII" concept will never be released and will have been turned into FFXV instead. But let's take this seriously for a moment, will we?
What would that mean? Would they simply change the name like what they did with Agito? I think it's not the case. It's a "main numbered game" and they're aware of how important those are, even when they have dozens of other games. So they must have done something about it. Maybe even the very basics of the game have been changed.
And if those have to be changed, you can't simply announce a name change with no other changes. Of course, it's not like not giving any information at all is much better. But at least, I imagine when they announce the name change (which should be the reason why they've been quiet about it) they will have already worked enough to, at least, be back on track.
And I'll put on my tinfoil hat. Expect a release date between june 2014 and june 2015!