MySQL on Mesos: today's database meets tomorrow's datacenter

Can anybody shed some light on why they're still using MySQL instead of MariaDB? MariaDB is supposed to be "ensuring drop-in replacement capability" with MySQL[1].

From what I gathered, the main reason people would want to move over to MariaDB is a concern over the Oracle licensing of MySQL, which prompted some of the original MySQL developers to create the MariaDB community fork.

I'm asking this question more from a greenfield perspective rather than as a continuation/expansion of an existing MySQL deployment.

[1] http://en.wikipedia.org/wiki/MariaDB