Most things are improved like the overall user experience. There are also features that are added, one popular thing is the Digital Wellbeing and the re-added Sunlight Mode feature in settings.
As you can notice in this browser is that the blue color of the site is blended to the notification bar. Icons from the home screen and app drawer are larger now.
Feature that is removed:
The semi rounded corners of the screen (if you noticed it).
That's my first impressions of the new update. Also, write your experiences, too, on the update.