Ansible doesn't give us any benefits over our current system. (Salt would be a better choice. Not a fan of YAML templating, to be honest, nor the tight integration with Python.)

Configuration management systems like Ansible and Salt and Puppet are fairly rigid; they are basically modular recipes for placing files and starting services on remote servers. What you get from Mesos (combined with its frameworks) is something that can run your services, keep them running, and handle the several state transitions that affect any running application: Transitioning from one version to another, for example, or restarting a failing app.

We've tried using supervisord as a stopgap solution, but it, frankly, sucks. Doesn't follow forks (no cgroups), isn't capable of cleaning reloading its config, can't do master/worker replacement, doesn't support syslog in any meaningful way.