I used to run CentOS in Dev/Test and then Red Hat in Prod. However, they have a habit of removing packages that compete with their commercial offerings, which forces you to either compile from source or to install from other repositories - for example, they removed Apache ActiveMQ because they offer JBoss AMQ. This starts to become annoying becuase all of a sudden you have multiple update processes to keep everything up-to-date, whereas previously, you had one. After being bitten by this at least twice, I shifted everything to Ubuntu. It's a shame - both CentOS & Red Hat are slow to move, but very stable. I was happy paying them support too ... but not when they kept making things more difficult.