In December someone at 5ch posted a supposed leak pertaining to Atlus, that looked like this:
As I'm writing this I realize that it was posted 5 days before Granblue Fantasy Versus was revealed.
So this was already looking pretty credible, as there were seemingly no rumors about that game going around beforehand.
Then the other day, a dataminer found this in Smash bros U:
Menentoes and Jack kinda line up with "Mementos" and "Jack" from the earlier leak.
So if all of these are true, it gives us quite a bit of future information.
The biggest one for me would be Persona 5 Arena, as I've been hoping for that game to be a thing.
But I have to say that if Mementos really is the Smash stage for Joker, that seems like one of the worst picks they could have made from a game with so many interesting locations...
I'll reserve my judgement until I see it, but it sounds a bit disappointing.