As we all know that there are different tools, e.g. Hyper-V Manager, Virtual Machine Manager and System Center Operations Manager (SCOM), you will need to manage the Hyper-V environment and soon you will find out these three tools are sold separately but not sold as a bundle.
Below are excerpts from the whitepaper of A VMware Administrator’s Guide to Hyper-V, written by Chris Chesley at Vkernel. You can download the document here: http://www.dabcc.com/downloadfile.aspx?id=863
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# Differences between VMware and Hyper-V
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Over-committed resources
One of the big differences between VMware and Hyper-V is the ability to over commit memory. In VMware you can assign more memory to virtual machines than physically exists on the host or resource pool. The idea is that the virtual machines will not use all their assigned resources at the same time. Assigning more memory than is available can increase your guest density (more guests running on the same hardware. More VMs on the same physical hardware means a better return on what you paid for the hardware and virtualization software.
Hyper-V will not allow the administrator to over allocate memory. While this may limit your ability to achieve higher density, it also means you can always count on the provisioned memory to be available. There is still a lively debate going regarding memory over committing and if this is beneficial or problematic in a virtual environment.
You can over commit CPU in both VMware and in Hyper-V.
Resource counters
VMware has memory and CPU metrics that are not available in Hyper-V. Specifically these are CPU ready, memory ballooning and swapping. CPU ready is a measurement of how much time a virtual processor has to wait for a physical processor to run on. Memory ballooning and swapping are both needed by VMware since they allow memory over committing and need a way of taking memory from one guest and giving it to another. It is also needed to give more memory to guests than is available on the host.
DRS and TPS
Distributed Resource Scheduler (DRS) and TPS (Transparent Page Sharing) are only available in VMware. DRS will either move virtual machines from one host to another or will make recommendations that you move them based on resources that are used and available on the hosts. TPS is a method where VMware will recognize memory pages that are used by multiple systems and not load duplicate pages. Instead it will load the memory pages once and then provide pointers to all the guests using those pages. It can offer up to a 30% savings in memory utilization if an administrator pays attention to what OS and applications are running on particular hosts and groups them together.
HA
High Availability (HA) is a feature of VMware where they will restart guests on a different host if the system they are on goes down or loses contact with VCenter (VMware’s management interface). Microsoft Hyper-V servers can be configured to be part of a Microsoft failover cluster which offers the same functions as HA from VMware.