MS will only leave the gaming market under one of 2 conditions
1) Sony leaves first
2) They no longer have their cash cows of Windows and Office.
Whilst I could easily see Office losing prominance to Google docs (if Google ever make it good), Windows is here to stay. MS will always have enough money to stay in the video games market. They have to stay in there to stop Sony winning the battle for the living room.
Nintendo will not leave any time soon. Even if their home console hardware sales dried up, they will have portable hardware dominance for a long time to come, and they would always make a killing from software regardless.
I doubt Sony will, but it is much more likely than the other two, so I suppose they get my vote. Regardless, even if they did quit the hardware market, they would continue to make games, either for another console, or for their phones.







