Microsoft's next big client operating system, Windows 8, will be out by October 2012. The operating system will be first made available to enterprise customers and hardware partners as early as by August, while the general public will have access to it in October. Along with availability to enterprises, Microsoft will commence the Windows 8 Commerce platform, which means developers of apps for the Metro UI can start monetizing their works. Windows 8 will get its big sales push at this year's Christmas sales season, when the software will be sold through major sales channels, such as retail, OEM (pre-installed) and special (student, university, government). For those who didn't quite get blown away by Windows 8 (through its Consumer Preview), Windows 7 will be supported looking deep into this decade. The operating system has currently passed the 640 million mark for the number of licenses sold, making it the best selling OS in computing history.