In a nutshell, OpenStack is a framework for providing developers with cloud-style APIs and tools on top of a choice of infrastructure technologies, but does NOT provide the underlying technologies themselves. You still need a hypervisor.
All your enterprise features like policies, governance, compliance, and not to mention your common expected management functions like snapshots, backup and DR capabilities.
What's the challenge?
Scripting through API calls, finding the right drivers to integrate with your compute, network and storage virtualization stack.
Where's the bacon?
VMware Integrated Openstack (VIO)
VIO gives you a choice of how you want to consume OpenStack, either through a tightly integrated
product (VIO) or a loosely integrated framework via distro partners.
VIO pulls in all the expected management capabilities, plus the additional features of the vSphere platform, integrated drivers for the network, compute, and storage that integrate with the APIs, all of the policies, governance, compliance, etc... reducing the overhead of custom development costs for a snowflake deployment.