[ryanfitz]

I bake ami using both packer and ansible and then do blue/green deployments using asgard from netflix. Asgard streamlines the whole process of creating a new autoscaling group, ramp up new instances and then cut of live traffic to the older instances. They also expose a simple http api to fully automate deploys.

I have been doing continuous deployments baking ami's with asgard for a couple of years now and have had great results.