The Xbox 360 sold out completely at release and by the end of September 2006 had sold 6 million worldwide.
Due to its early launch, the Xbox 360 has a one-year lead on both of its competitors, Sony's PlayStation 3 and Nintendo's Wii.
Microsoft is predicting that with the Xbox 360, a greater market share, yearly revenue through their Xbox Live service, and falling hardware costs will eventually make system sales profitable.
Xbox Live Silver is free of charge and allows users to create a user profile, join on message boards, access Microsoft's Xbox Live Arcade and Marketplace and talk to other members.
Microsoft XNA is a set of tools and technologies that includes XNA Studio, which provides versions of key production tools such as asset management, defect tracking, project automation and work lists.