As a passionate ICT person, I work with multiple virtualization products including Microsoft Hyper-V and VMware vSphere.
At home I’m running Server 2012 with Hyper-V in my home lab and even though it works perfectly, I miss the option to be able to run multiple other hypervisors beneath it like by example multiple Hyper-V, VMware ESXi or Citrix XenServer instances.
With VMware products like VMware Fusion, VMware Workstation you can enable this with only a couple of minor adjustments as described in these great articles:
For me personally, I’ll stay with my Hyper-V based home server and my Windows 8 Client with Client Hyper-V installed. For testing purposes however, I’ll have to use VMware Workstation 9 on my Windows 8 machine. (even though I have Client Hyper-V installed). This way I can still run other hypervisors when needed.
I still hope though that Microsoft will add a similar feature to Hyper-V in the future.