At Drupalcon Global Dries announced Automatic Updates as 1 of 5 strategic initiatives for Drupal 9.
Automatic Updates is an existing initiative that has already produced a contributed module that can provide updates for non-Composer based Drupal 7 and Drupal 8 sites.
The next phase of the initiative is to add support for updates of Composer based sites to Drupal 9. Currently the initiative is focusing on moving update readiness checks and other supporting functionality from the contributed module into Drupal core.
Learn about the initiative and how you can help