The MariaDB release is said to incorporate all of MySQL 5.1.42 functionalities plus additional features put out by the MariaDB team. The end goal, according to Monty is to replicate all the MySQL functionality and add features needed/desired/wanted by the end user community.
MySQL founder, Monty Widenius, branches and builds complete port based on Maria storage engine.
Well it didnt take long for Monty Widenius, MySQL founder, to branch bring one of his personal projects to fruition and develop his own version of MySQL. With help from other Sun employees, as well as community members, Monty has built upon the Maria storage engine and release MariaDB (now release 5.1.42).