Teams can already work from the same contact records with per-person access. The bigger collaboration surface, a unified inbox and finer permissions, is still being built.
Shared contacts and collaboration are available on Pro right now. The shared inbox, delegated work, and role-based permissions described below are in development and not yet available.
Roles that say who can see which contacts, who can send on the team's behalf, and who can change the things everybody depends on. Today the control is per contact and per person.
It is the part that works now, and it is what the rest gets built on top of.