As of right now, we only know of some functions they're working on for privately-owned housing (this being allowing upwards of 5 people access to decorating and/or gardening in your place, no word on whether that will include teleport privileges just yet), but ultimately we're still mostly in the dark as to what specifically is going to be implemented in the next housing update.

Hopefully we'll get all that info when they broadcast the next Live Letter next week from TGS, as well as 3.1's release date (but that may not even be released until the Hiroshima event next month, as Yoshi-P said either the 14-hour anniversary live stream, the TGS Live Letter or Hiroshima would be the announcement).