If you are going to use MariaDB to replace existing implementation of MySQL in production environment, then you will realize changing a DBMS to one another has never been easier considering the risks of incompatible supported features and functionalities, unpredictable development time and resources, migrating a huge amount of data and so on. MariaDB has already succeeded as a "drop-in" replacement for MySQL and is truly open source and more optimized, faster and safer.
Though being mentioned that Migration might become difficult after 2015, below is a few steps which I believe is quite simple to install MariaDB replacing MySQL on Ubuntu 14.04.x as I came across the same requirement switching MySQL 5.5.5 to MariaDB 10.1.14.
