Microsoft created quite a stir earlier this month when it was revealed that the Windows 8 Store would block titles that received a PEGI 18 rating in Europe. Games with an ESRB rating of Adults Only (AO) were also banned from the digital store in the US but the decision created a gap between allowable games in the US versus overseas based on how the ratings boards grade titles.
As it was set, Mature (M) titles like Assassin's Creed, Bioshock, Call of Duty: Modern Warfare 3 and Skyrim would all fall under the PEGI 18 rating (that also includes adult titles) and thus wouldn't be available to purchase in the Windows 8 Store.
This decision had no bearing on third party titles purchased elsewhere but as Windows corporate VP of web services Antoine Leblond points out, it basically ended up disqualifying games in the European store that rated ESRB Mature in the US.
Microsoft will instead move to a system that allows games with an equivalent Mature rating to be sold in the European Windows 8 Store.
The error has since been rectified but don't expect to see changes reflected in the Windows 8 Store anytime soon. Games that have been tagged under the old system won't be showing up in the Windows 8 store today or anytime soon.
Leblond said Microsoft plans to "flip the switch" sometime in December meaning if you're dead-set on picking up a new title to play before the holidays that has a PEGI 18 rating, you're best getting it from a third-party source.