When Oracle got their hands on MySQL, original developers fled and forked MySQL into an open-source product MariaDB. It remains fully compatible with MySQL, but its development is completely transparent, unlike MySQL nowadays. Notable users of MariaDB include Wikipedia, Facebook and Google.
It is an enhanced, drop-in replacement for MySQL and can be safely used instead of MySQL. Latest versions include GIS and JSON features.
As MariaDB is derived from MySQL and is compatible in connection mechanisms with it, all our applications that work with MySQL will work perfectly with MariaDB database.