Every call for Ballmer's ouster ignores two important points. He is the second largest shareholder. His college buddy is the largest.
No analyst has clout with the shareholders. Nobody inside does either.
What I see in Sinofsky's departure is a clear signal that the type of politics which this article assumes to be the proper way of creating succession is being deprecated within Microsoft. What I mean is that the argument is premised upon the idea that rivalries at the executive level should be acceptable.
Just because that is the way most public corporations work, doesn't mean it ought to be the way. Gates and Ballmer have been running Microsoft for thirty years. They've got real long term interest in creating a sustainable culture.