Why 30 Rock and not Studio 60
It is really simple, NBC doesn't own Studio 60 and since they don't own it they won't let it be a success. See this TVSquad
article for all the details. This is the classic boneheaded management maneuver that I will never understand. Studio's know that the 10 PM time slot is tough, yet Studio 60 consistently outscored 30 Rock when 30 Rock was in the very 9 PM time slot that Studio 60 was supposed to occupy.