To me a virtual server is still a server. You should probably add the virtual servers to your physical servers because the host servers are also separate operating systems.
you can view this in numerous ways, Microsoft OS is called Windows server so is server a physical entity or a installed software?
in virtualisation you manage Virtual machines which are sometimes called virtual servers or virtual desktops, in this sense you are manageing more servers as you will get more virtual machines in your infrastructure because we are human! to this end it means we can put more on a single peice of hardware so as humans we do, its only when we get to stretching point we stop and back track. (Server sprawl)
in the end your definition of server is what matters, if its physical watch for redudancy as your all looking after a lot less, if its operating systems then you should ask for a payrise for all the test and demo servers you have made but not deleted yet but are still on your books as managed servers! 🙂