The forums will be made once the user account system has been made. The estimate for this is September 2017.
Update (01/02/18): Still not happend, Little free time to devote to PERT.IS Central site latly. Can't see this happening within the next year sadly.
Update (27/12/18): Probabbly not going to happen in the foreseeable future. A group on a social network might be easier, if you'd like that then please let support know.