I agree with the other comments here that this is highly confusing, as evidenced by the contorted explanations for how it works. Surely it would be easier to just say Yammer is becoming Viva Engage and we are adding these new features. If Viva Engage is Yammer then why are two apps needed that do essentially the same thing? MS is terrible at this overall, constantly putting out new apps that duplicate functionality so its unclear what users should use and when. The confusion over Planner, To-Do and Outlook tasks is a case in point, why can't there just be a tool called Tasks that combines these together into one place? MS finally seem to be moving in that direction by depreciating outlook tasks and adding Planner tasks to ToDo but its taken years, don't make the same mistake with Yammer and Viva!