Red Hat Enterprise Linux 8.0 is now GA!
Here are some things to consider:
RHEL8 uses the dnf command instead of yum with an identical syntax (yum is an alias for dnf).
The Btrfs file system, once in technical preview, is no longer available.
Most of the system scripts are still written in the Python language, however version 3.6 will replace Python 2.7. More details here: https://developers.redhat.com/blog/2018/11/14/python-in-rhel-8/
LDAP: The OpenLDAP package is no longer available. You'll have to use the 389 LDAP server or something else.
You cannot remove NetworkManager from your configuration. This was already the case with the Gnome graphical environment in RHEL 7.5.
KDE is removed from the desktop. KDE is deprecated according to the RHEL 7.6 release notes.
A new mechanism called application stream is introduced. More details are available here: https://developers.redhat.com/blog/2018/11/15/rhel8-introducing-appstreams/