All of our infrastructure is CentOS (or derivative) in every single place I've ever worked. I used a mix of Mac and Windows at home and work. I don't want a linux distro with UI overhead.
Ubuntu server's default UI is a bash shell.
http://www.ubuntu.com/download/server
Not saying you should be switching over now because of this, but come on.
Case in point, why does MySQL automatically get started (in an insecure state, mind you) when installing from the official repos on Ubuntu? And standard Apache and Nginx configuration patterns (and the changes from 10-12-14.04) sometimes make me want to give up supporting Deb/Ubuntu!
Re: apache: at least apache on deb-based systems keeps the same name everywhere, and you don't have to remember which part of the system calls it httpd and which part calls it apache :)