[s3_gunzel]

The majority of people using CentOS either had fewer than 16 servers, or were in a larger business where RHEL could easily be afforded.

You do realise with the advent of Virtualisation that this is still a non-starter for a lot of people - including me.

I have, at present, 11 production servers - they're all virtualised, but that's 11 installs of whatever OS (in my case, Ubuntu LTS). Convention is that you're supposed to have one server PER ROLE - so if that's Jenkins, or an issue tracker, or a database, whatever. One role.