The new release is making its way to Fedora mirrors as I write this. The notes are up.
Distro-syncing specific subsets of packages is finally here. Also 0.4.18 marks the move to objectified groups, something Yum did in 2012. Things might look a bit shaky on the groups front for some time while the precise semantics settles but the basic operations work and support for installing optional packages has been added again. Moreover, the changes provide new API that allows the DNF Anaconda payload to exclude packages from transaction as the user wishes.
API also sees some spring cleaning of parts that we’ve deprecated and kept in the cellar since last December.