I second this many times. The APIs were so inconsistent. I had to go through many hooks just to get the data I wanted. Openstack is nice, but Openstack community tried to create an open AWS. The problem is, everything gets so modular and too many components to deploy just to get Openstack working.

It's a PaaS for IaaS foundation. Unless you have the resources to line up and support Openstack, I recommend just build on AWS/Google/Azure/Rackspace/Heroku/DigitalOcean, you name one.

I wonder if big customers such as Bloomberg ever regret / think of moving to public/private IaaS.