Neowin writes Windows 8 will offer Hyper-V 3.0, a new virtual hard drive format named VHDX, and many more new features.
According to Robert McLaws at Windows Now, the new features bring a larger scale version of virtualisation than what we have seen before in a Windows operating system. The new virtual hard drive format allows a total size of up to 16TB of data, which is a significant improvement from the VHD format, and Microsoft has also included support in Hyper-V for more than four computing cores, ultimately benefiting those with a lot of computing power. Overall, Mr McLaws has uncovered the following new features in this build of Windows 8:
Virtual Fibre Channel Adapter
Storage Resource Pools
New .VHDX virtual hard drive format (Up to 16TB + power failure resiliency)
Support for more than 4 cores! (My machine has 12 cores)
NUMA - Memory per Node, Cores per Node, Nodes per Processor Socket