I think Microsoft would be stupid to sell off the xbox division mainly because I think it can be their next Windows well not the xbox but live. All their most successful products exist because of windows such as office. Live could be the same, things like the Zune marketplace are worthless on their own but when you can combine them with a service like Live you can have some decent success.
I could be completely wrong but I really think Microsoft does (or at least should) think of Live in the same way they do Windows








