Google has published page with a description of the new version of Android on your site.
I will not list all the features of Android 10, the main ones can be seen on this page. From what we have not yet seen, there is a dark theme in the Gmail and Google Maps applications.
At the same time, Google has updated the logos of all branches and services of Android – Android TV, Android Auto and Android One.
Old / new logos
Firmware with the final version of Android 10 has already begun to spread as an OTA update.