Katsura Hashino recently spoke with Dengeki Magazine where he revealed that they are “…preparing to start work on the next Persona.”
No details were released, but Hashino did give a bit of a hint of what to expect. ” I want to add things that are being expected of the series. I also want to change things that can be changed within those boundaries.”
Sounds like your typical plans for any sequel. It looks like it will be awhile till we see any concrete details about the title though.