A new report says Microsoft has not ruled out major options for Xbox, including restructuring the gaming unit, making it a wholly owned subsidiary, creating a joint venture, or potentially spinning it out in the future.The report also claims Microsoft leadership has approved a plan to spend more on major franchises like Halo, Fallout, and Elder Scrolls, as Xbox looks for a stronger path forward.So what would an Xbox spin-off actually mean, and how realistic is it?