Yesterday I had my fears confirmed about the Drupal Automatic Updates initiative. It requires sites to be able to modify core Drupal files. While this makes it easier to fix vulnerabilities, it is not something you want when your site is actually being attacked. The best way to protect against someone exploiting a vulnerability to modify your Drupal core files is to change the file permissions so that your site cannot modify them.
Today I was listening to Talking Drupal #168. The topic was how to ensure that open source project developers can afford to provide updates to their users. As an open source developer myself, I have to disagree with the premise that we should support a distinction between users and developers. The projects that I develop for are the projects that I use. As a user-developer, I do not care how many users a project has. I care how many user-developers it has.
I set up Dreamhost cron jobs to run
drush cron for two different sites running Drupal 8.0.3. One of the cron jobs worked, but the other failed with a syntax error. Drupal 8 requires PHP 5.5.9 or later, and the default version of PHP for one of the sites was 5.4.42. Changing the default PHP version in .bash_profile and .bashrc did not fix the error.
If you add a private files directory after installing Drupal 8.0.3, you will get a warning on the status page saying it is not fully protected and to see https://www.drupal.org/SA-CORE-2013-003 for information about how to protect it with an .htaccess file. The message shows up even if the directory is not Web-accessible. Ignore it. The .htaccess file will be created automatically after caches are rebuilt.