Terms used:
Inner circle – your team your project
Outer circle – the rest of your organisation
External circle – outside your organisation

Common current scenario.
Microsoft Teams used for inner circle collaboration and communication.
Outlook used for communication with the outer and external circles.

Possible future scenario.
Microsoft Teams used for inner circle collaboration and communication PLUS structured collaboration and communication with select people and groups from the outer and external circles. This change is due to Shared Channels.

Outlook used for communication with the outer and external circles PLUS ad-hoc or unstructured collaboration with select people and groups from the outer and external circles. This change is due to Loop components, with the collaboration feel of Outlook being increased by reactions and direct access to apps into Outlook.

I love these changes, but I can see potential for end users being confused if organisations let these features role out without clear guidance.

Learn more:
Shared Channels: https://supersimple365.com/teams-connect-shared-channels/
Loop components in Outlook: https://supersimple365.com/loop-components-in-outlook-mail-preview/
Reactions: https://supersimple365.com/new-outlook-reactions-and-new-notification-experience/
Direct access to apps into Outlook: https://supersimple365.com/new-location-for-key-functions-and-direct-access-to-other-microsoft-365-apps-in-outlook/

Of course there are/will be exceptions, including those created by the use of Teams Chat.

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