The latest version of the Windows Operating Systems, Windows 8, was officially released on October 26, 2012.
Football Manager 2013 works on Windows 8 but ONLY in desktop mode (this can run both on a desktop or laptop but NOT a tablet).
This means that FM13 will NOT work on Windows RT, Windows phone 8, the cheaper "ARM" versions of the Microsoft Slate or any device using the cut down operating system.
When the Intel version of slate comes out it may work on it, but Sports Interactive will not be offering support on it or claiming that it does work in any way. It is not designed to be played on a tablet, and the game does not have touch screen control. Nor do they have any plans, whatsoever, to support those functions or the system. Or the Windows 8 RT operating system.
In addition, sadly you cannot post to Facebook in-game and cannot access the in-game manual via Windows 8.
Football Manager 2013 is the only one of FM titles that was tested on Windows 8. Sports Interactive will not be offering support for it on earlier versions of the game.