But given that support for VHD files is now not only part of virtual server / hyper-v but core function of the operating system (R2, Win7) which supports mounting and unmounting them DIRECTLY from the file manager, the missing support for VHD files starts itching a little, or?

I have some scenarios where I Would love to mound differential VHD files - basically to boot workstations from a central base image. In other scenarios I do not care (basically: Hyper-V, where I will use a clustered shared storage for the cluster).... but support for VHD files would definitely be nice.