No, I think people come to him with great ideas and he can see how they can be turned into something that is useful, elegant and easy to use. Then he browbeats them until they get it right.
The truth is SJ has always been a good idea man and a great judge of style and useability. He has good ideas and he's really good at refining good ideas or even being a judge of other ideas. He just isn't the one to implement the ideas. He's not a coder. He's not an engineer. He delegates and he knows what he wants and he has an incredible vision for the future. It's that vision for where the company is headed that makes him important. I'm sure incredible ideas come to him on his own or from others, but it has to fit the model, the plan, the vision. He's a leader. And getting better at it with age.
I own Apple stock, and if he ever announces retirement, I will immediately be dumping quite a bit of it. Doesn't matter if Steve isn't as important as many beleive. It matters that that is the perception. Before he retires, if he ever retires, he needs to slowly slowly slowly tone down his role at the company.