Online sources are reporting that Microsoft is playing safe with their Windows Store platform that would arrive with Windows 8.
The company is not planning to support mature games for sale through the Windows Store.
This means M rated games in USA and 16+ PEGI rated games in Europe would not be available through this online app store.
It is not clear why Microsoft chose to take this route considering they could have placed enough parent control options to prevent minors from ordering these games.
Maybe they would enable support for such titles in the future once the platform has seen enough real world testing!