I'd say in a situation where a good curriculum exists, teachers need to take the role of coach and motivator.
I couldn't agree more about the difficulty in creating a good curriculum. The big question in our minds becomes whether or not a decentralized and distributed system can create great curricula and reduce the pressure on that lone teacher. I believe the answer is yes and with such a system we end up with better courses.
I'd say motivation is a big one. It takes motivation to push yourself to learn from books. I prefer to learn that way myself. But plenty of students don't have it or don't see the value. A teacher or mentor can make a huge difference to students in that situation.
I believe open teaching creates transparency that will enable us to better identify the "bad" ones and allow them to improve their craft through feedback loops. This openness will generate more and better teachers. Those that simply lecture to masses are likely to be replaced because they don't provide true value to students. (disclosure: I'm co-founder of trinket.io.)
I am really excited to be a part of the Fall 2013 class. The startup community and ecosystem in the Raleigh/Durham area has grown significantly over the past several years. The diversity of this class as well as the distance some of them traveled to be a part of it is a testament to the support and opportunities available.