Settings > Activity History
The Timeline shows a list of activities from all your devices, and may be desirable for some users. However, if you don’t like the feature you can turn it OFF and the Task View should behave as normal.
WIN + H
The new feature enables you to dictate to apps which do not specifically support dictation. A good mic will improve the accuracy of transcription. One caveat: this feature works only with the locale set to EN-US.
Settings > System > Focus Assist
You can control all those app notifications based on three scenarios: a specific “quiet time” time-frame; while duplicating your display, which is useful while presenting; and while gaming. In each scenario, you can opt to: a. keep notifications off; b. display private high priority notifications (you decide who’s next); and c. alarms.
Another (unrelated) relief is the reduction in Windows Defender auto notifications.
This is a major update and there are a ton of other features: these include PWA support, quick Bluetooth pairing, improved text scaling, nearby sharing (akin to AirDrop), some Fluent Design touches to make the UI more attractive (yes, I’m that shallow), and tab muting in Edge (if you are among the six people who use it).
How-To Geek is a good place to start learning about them.