System Center Virtual Machine Manager (VMM) 2012 delivers industry leading fabric management, virtual machine management and services deployment in private cloud environments. VMM offers key new features that include hypervisor creation and management, network management, storage management, private cloud creation, self-service usage and service creation. It features deep investments in server application virtualization, service design and service modeling all of which can be used to efficiently offer an on-premises private cloud.

[UPDATE for 4/23/2012] - The information on the supported upgrades below is incorrect and out-of-date.  The RC download description was updated last September, but this blog entry did not receive that update.  The information on the SCVMM blog post supersedes the information here.  Sorry for the confusion.

Feature Summary:

• Fabric Management
  • Setup Upgrade
    • *New in RC: The following upgrade paths are enabled (supported only for TAP customers in production):
      • VMM 2008 R2 SP1 --SC VMM 2012 RC -- SC VMM 2012 RTM
      • SC VMM 2012 RC -- SC VMM 2012 RTM
  • Hyper-V and Cluster Lifecycle Management – Deploy Hyper-V to bare metal server, create Hyper-V clusters, orchestrate patching of a Hyper-V Cluster
    • *New in RC:
      • ISO or CD-based OSD for environments with DHCP without WDS
      • OSD will now convert dynamic to fixed type of VHD destination
      • All network adapters on host can be configured during provisioning
    • *New in RC:
      • Ability to bypass cluster validation during cluster creation
      • Run cluster validation reports on-demand
      • New Cluster status tab to view an aggregated status and a cluster validation report
      • Ability to see current CSV owner in the properties of the cluster
  • Third Party Virtualization Platforms - Add and Manage Citrix XenServer and VMware ESX Hosts and Clusters
  • Network Management – Manage IP Address Pools, MAC Address Pools and Load Balancers
    • *New in RC:
      • Simplification of the logical networks in the Fabric workspace
      • Ability to see IP addresses that are in use from a IP pool
      • Added support for Microsoft Network Load Balancer
      • Gateway and DNS are no longer mandatory fields for logical networks
      • Load balancer can now support affinity to logical networks
  • Storage Management – Classify Storage, Manage Storage Pools and LUNs
    • *New in RC
      • Create persistent sessions to iSCSI array and logon initiator to array
      • Better scalability of storage operations - LUN create, snapshot, clone, masking, and unmasking
      • Option to create storage groups per cluster (BETA only supported creation of storage group per node in a cluster)
      • Enablement of MPIO feature when provisioning a new Hyper-V server
      • Automatic MPIO device claim
      • Support for arrays that implement OnePortPerView
  • Update Management- Keep your VMM Fabric Servers (VMM roles, hosts, and clusters) up-to-date with patches.
    • *New in RC:
      • Share a WSUS root server between System Center Configuration Manager 2007 R2/ System Center Configuration Manager 2012 Beta
      • Hyper-V Cluster Orchestration- Nodes put into VMM Maintenance Mode can be set to trigger Maintenance Mode in Operations Manager.
  • Resource Optimization
    • Dynamic Optimization – proactively balance the load of VMs across a cluster
    • Power Optimization – schedule power savings to use the right number of hosts to run your workloads – power the rest off until they are needed.
      • *New in RC:
        • Set Operations Manager Mode for powered down hosts
    • PRO – integrate with System Center Operations Manager to respond to application-level performance monitors.
      • *New in RC:
        • Support added for System Center Operations Manager 2012 Beta
        • VMM will ship two sample PRO Packs: Cluster scale out and Service scale out MPs
• Cloud Management
  • Abstract server, network and storage resources into private clouds
  • Delegate access to private clouds with control of capacity, capabilities and user quotas
  • Enable self-service usage for application administrator to author, deploy, manage and decommission applications in the private cloud
• Service Lifecycle Management
  • Define service templates to create sets of connected virtual machines, OS images and application packages
    • *New in RC:
      • Service Designer and Specialization UI enhancements
      • Added ability to use Service Template Patterns
  • Compose operating system images and applications during service deployment
    • *New in RC:
      • IP-based provisioning
      • New application instance view
  • Scale out the number of virtual machines in a service
  • Service performance and health monitoring integrated with System Center Operations Manager
  • Decouple OS image and application updates through image-based servicing
    • *New in RC:
      • Streamlined ability to enable OS VHD updates to a Service Template
      • Publish updated Service Templates in order to update Service Instances
  • Leverage powerful application virtualization technologies such as Server App-V

Whew! Go get it @ http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=27252.