I wonder how many people here would actually benefit from running CentOS. The first thing I need to do on a new CentOS machine is install newer versions of PHP, Python, and Ruby. It's kind of becoming a pain in the ass.
I use CentOS and I like it because I get both the underlying structure and packages of RHEL but it doesn't get in your way (as Ubuntu or Debian try to) when you want to step off the beaten track and do things by hand. In Debian-based distros, not using the package manager feels like heresy.
On the other hand, with CentOS you have to step off the beaten track and do things by hand more frequently - for example, where CentOS comes with Exactly One Python Version, and everything Python-related is packaged against it, Debian comes with multiple Python versions, and anything Python-related you install automatically gets set up to work with whatever (compatible) Python versions you have installed.
I think the primary reason for its existence is complete binary compatibility. I think they may even say that on their website. If you don't need the compatibility, there are probably better options.
