In Asana you can:
These points are the top reasons why I can't move to Ryver yet!
PS. A thought about privacy: The person moving or sharing a task or post has the responsibility to do so without accidentally making a private conversation or task "public". This needs the same "administrative control sense" as when sharing paper documents or e-mails within an organization. I believe that most people will handle this without any problem.
Customer support service by UserEcho