Currently a list of supported guest operating systems is not provided, one should be added.
An interesting area to explore here is not just confirming Hypervisor support (after all a guest that runs on base-RHEL KVM or RHEV should also run on RHOS) but also ensuring we guide users on how to create and/or where to get RHOS friendly disk images. Based on ask.openstack.org and the openstack mailing lists creation of Windows guest images suitable for use with RHOS is something that is particularly under-documented or at least misunderstood.