GitHub User: bradenwright
I use chef server (open source) and got rid of Capistrano for my deploys. Chef has a "deploy resource" http://wiki.opscode.com/display/chef/Deploy+Resource
Few things I really like:
1) Its a pull architecture, so you can cron machines to check back in and pull updates for production. But from the cli (knife) you can use the search feature and run whatever command you want. So for testing env I use it like cap (and essentially have a push deploy)
2) You can rollout upgrades to your application stack as well as your code. This is really nice for testing b/c it has environments so you can roll out new recipes to testing envs and then to production. Recipes etc are also usually maintained in a git repo.
3) I really like that it can be used in so many places. I use it to setup my laptop which runs ubuntu, virtual machines for testing environments, and a physical hosted server. I have also started to play with it in the cloud a little. For the physical machines I run a bootstrap command to setup the machine, with vms & cloud there are plugins that will also provision machines. If you write your recipes to scale and add monitoring... you can actually have you app scale on its own!
I have been playing with it for the last 6 months or so (on and off). I will say that chef like rails has a learning curve, but it gets easier... And its very easy to see the power. Infrastructure as Code gotta love it