A post on Critical Detail takes a critical look at the closed distribution model in Windows 8 and Windows RT, speculating about how this will impact software distribution over the next 20 years. As noted on Kotaku, this includes a rule against selling adult content through the Windows 8 Marketplace, saying: "Your app must not contain adult content, and metadata must be appropriate for everyone. Apps with a rating over PEGI 16, ESRB MATURE, or that contain content that would warrant such a rating, are not allowed." While this will not impact U.S. users much since almost no games are ever rated "AO," there are lots of games with a PEGI-18 rating in Europe this will prohibit. There are a number of reasons this will not impact hardcore gamers in the short term, as they are unlikely to be rushing to adopt the new Windows, unlikely to make a tablet their primary gaming machine, and unlikely to make the Microsoft walled garden the place they buy their games, but the trend this represents is certainly troubling. Update: Corrected to be clear the rule will prohibit AO games in North America, not "M" rated games. Apologies for the confusion.