Eco-technic Dreams

Okay, http://www.ted.com/talks/view/id/104 and skip to minute 18. McDonough is talking about something which is completely self sustained, or nearly so, I guess the only down fall of all this is the initial inputs, right, the concrete and steel or whatever is to build the city in the first place. THen there is also the completely planned thing, there needs to be room for innovation. But as a whole, does this seem feasible, possible to people? More importantly, does it seem like a good thing?