I feel that Triple H will be running the show. So many wrestlers right now have said that he really is running the show now, including Kurt Angle. I don't particularly believe that is true, but I think Triple H is highly involved in the company and will very, very likely be running the show when Vince passes. More than likely, we'll see Stephanie as the new Chairman and HHH as the CEO.
Now, I know at the moment Shane is supposedly only an on screen character due to him leaving the company and selling his stock. I have no doubt that over the years, he will be more involved. But due to their loyalty to the company, I see those two running the company mainly afterward.
I would keep this in mind too, if Vince decides he is running the company until he dies, be prepared to be waiting for a very long time for a chance. Vince is a healthy guy and I think he has a lot of years left in him.