With this update you will be able to choose your preferred means of Teams notifications delivery, either via the Teams built-in notification system or via your native OS notification system.
How will this effect you and your organisation?
If you wish to change notifications from the Teams app to the native Windows OS notification system, you can do this in your Teams notification settings.

Image is not our own. Image courtesy of Microsoft, taken from Message Center email: Windows 10 native notifications in Teams
When can you expect this to happen?
Roll out will start mid January through to mid February.