Nobody killed Tony, he's still out there. It was the viewer who was whacked since we saw it from our POV not Tony's.
Not necessarily true. If you watch the last episode everytime the bell rings and someone comes through the door we see Tony look up and then we go immediately to his vantage point (this happens numerous times during the final scene). When Medow walks in we see Tony look up and then, when we are to shift to his point of veiw...... Black and everything stops. Tony is dead
