Minimal downtime when moving virtual machines from one host to other host servers  .

High Availability 

Providing the support for host-to-host connectivity and enabling users to cluster all virtual machines running on a host.

Server Core role

Hyper-V is now available as a role in a Server Core installation of Windows Server 2008.

Integrated into Server Manager

Hyper-V is integrated into Server Manager, where customers can now enable its role.

Live Backups with VSS

Hyper-V includes support for Volume Shadow Copy Services (VSS), which enable us to take Live Backups of running virtual machines in terms of snapshots.

VHD tools

Hyper-V also includes support for VHD tools, which enable compaction, expansion and inspection of Hyper-V-created VHDs .

Linux integration component

Components of Beta Linux integration  are now available for SUSE Linux Enterprise Server 10 SP1 x86 and x64 Editions. The integration provides improved performance by enabling Xen-enabled Linux to take advantage of the VSP/VSC architecture. Beta Linux Integration components are available for immediate download through connect.microsoft.com.

VM Manageability

Customers can easily import/export virtual machine settings to take backups of configurations and to clone the virtual machine characteristics across different hosts.

Improved performance

Hyper-V includes several fixes to improve performance.  The integration components are automatically included by all new Windows Server 2008 virtual machines .

Improved access control with AzMan

Hyper-V now includes support for Authorization Manager (AzMan), which enables Role-Based Access Control models for better administration of the Hyper-V environment with increased security.

Remote Management

Hyper-V supports remote management and also provides a Hyper-V MMC only installation option for a separate management node.

Increased Virtual SCSI support

Hyper-V includes support for up to four virtual SCSI controllers per virtual machine, therefore enabling broader disk support.

Increased Memory Support

Hyper-V supports up to 64GB of memory per virtual machine.

Quick Reset

Hyper-V provides administrators the option to quickly Reset Checkboxes and Delete saved credentials that are used to connect to virtual machines.