Taken directly from MS Connect site:
Microsoft System Center 2012 Configuration Manager Upgrade Assessment Tool is a feature pack download that provides administrative users with information that they can use to determine if the operating system on computers that are managed by System Center 2012 Configuration Manager can be upgraded to Windows 7 or Windows 8. The previous version of this tool was the Configuration Manager 2007 Application Compatibility Toolkit Connector (ACT Connector).
· Retrieves device driver compatibility for installed peripheral devices and creates reports that you can use to determine which device drivers need to be upgraded to support the Windows operating system.
· Allows you to see which computers meet the recommended system requirements for Windows operating systems and to customize these requirements for your environments.
· Creates summary reports that you can use to see an enterprise wide view of operating system upgrade readiness.
· Allows you to create dynamic collections for an operating system deployment. The collection query rules can be based on system requirements, application compatibility status, and device driver status.
Please note that the Beta version of the Upgrade Assessment Tool requires the ConfigMgr SP1 Beta and the Application Compatibility Toolkit (ACT) 6.0 which is available in the Windows Assessment and Deployment Kit (ADK) for Windows 8.
More information and download link for the tool can be find on Connect site.