Windows 8 includes a number of changes to the parental control ratings systems supported by Windows Family Safety (aka Windows Parental Controls) for Win32 desktop games. These changes are now available on Windows 7 via KB2773072. It is recommended that all game publishers populate their GDFs using the latest Game Definition File Editor (GDFMaker.EXE) in the Windows 8.0 SDK rather than using the legacy DirectX SDK version which does not support these ratings changes.
For full details on these changes to the ratings systems and GDF-related tools, see the Windows 8 and GDFs blog post.
Note: The latest version of the Game Definition File Validator (GDFTrace.EXE) on MSDN Code Gallery has been updated for all the latest ratings system changes.
Update: The latest version of GDFMaker is in the Windows 8.1 SDK.