It was announced that MariaDB is now the default implementation of MySQL in the newly released Red Hat Enterprise Linux 7.
News of the Red Hat Enterprise Linux 7 can be found here.
And mention of MariaDB replacing MySQL as the default implementation is referenced in their release notes here.
The full change log entry reads:
- MariaDB is the default implementation of MySQL in Red Hat Enterprise Linux 7. MariaDB is a community-developed fork of the MySQL database project, and provides a replacement for MySQL. MariaDB preserves API and ABI