My hosting service utilizes CentOS. Whenever I set up boxes, it's often Ubuntu or Debian. Given the choice, I'd prefer a Debian-esque distro, but it's all similar enough to me to not make much of a difference.
I work at a large webhosting provider, we primarily use CentOS as a hosting platform, for my personal use I prefer Debian and this is a common secondary choice here for custom webservers or virtual servers; we use CentOS because it has full support for cPanel.