Keeping servers updated?

I have a small but growing personal fleet of Debian servers that I want to keep updated on a regular basis and wondered what the best route was to go with doing this, whether automated or semi-automated.

I'm currently taking a hard look at doing this with Ansible, as it seems like a nice tool, I wondered what others are currently doing though to see what other options exist. I've also used cron-apt with good success in the past, but I would rather have a more centralized system...

So linuxadmin's... how do you keep your server farms apt/yum/pacman/$packagemanager updated?