I have seen no mention from anyone in this thread about VMware's orchestration tool. Keep in mind that this tool is licensed along with vSphere so there is no additional cost. All of the other orchestration tools I have evaluated come at a hefty price. vCO is very powerful and I have as of yet not found anything I could not automate with it. It comes with plugins for most VMware products and also includes plugins which allow interatction with SOAP and REST api's, Active Directory, SSH, PowerShell etc... There are some attractive 3rd party vendors out there as well which have plugins including Cisco.
Another tool in your arsenal for automation is RabbitMQ. We have done some very limited testing but you can leverage it along with vCloud directors blocking tasks to do some really cool stuff. I believe this is also gratis at the moment.