Here are the recent changes to the packaging guidelines.
The packaging guidelines for enabling services by default were
significantly revised to emphasize that services starting by default
should fail only in exceptional conditions, and to provide additional
guidance for services related to hardware enablement.
The Python guidelines were modified to mention the %pypi_source macro
(available in all Fedora and EPEL releases) which conveniently expands
to the proper source URL for the package at PyPi.
The Python guidelines were modified to indicate that packages must not
own the top-level __pycache__ directory.
A small change was made to the Java packaging guidelines to specify a
dependency on javapackages-filesystem instead of javapackages-tools.