We just release a new project for initializing Windows cloud instances on OpenStack:
• Supports HTTP and ConfigDriveV2 metadata sources
• Provides out the box: user creation, password injection, static networking configuration, hostname, SSH public keys and userdata scripts (Powershell, Cmd or Bash)
• It’s highly modular and can be easily extended to provide support for more features and metadata sources.
• Works on any hypervisor (Hyper-V, KVM, Xen, etc)
• Works on Windows Server 2003 / 2003 R2 / 2008 / 2008 R2 / 2012 and Windows 7 and 8.
• It’s platform independent, meaning that we plan to add other OSs, e.g.: FreeBSD
• Written in Python
It's currently in beta status, we are looking for help to test it on various hypervisor / guest combinations. I'd be glad to answer any question (and fix any bug)! :-)
We did most of our testing so far on Windows 2008 R2 and Windows 2012 using ConfigDriveV2 metadata on Grizzly, but we plan to add more platforms to the tests soon.