ahug030 -- I read that you are considering Duke over Cal at this moment. I know nothing about Duke-- but I have to put in a good word for Cal. I am an undergraduate there right now and Berkeley is one of the best places I could imagine going to graduate school. It is a great area, good people (although it true that the locals are a little crazy sometimes-- in an amusing way), and a very flexible and relaxed department overall. All of the graduate students I know are happy here. But the city of Berkeley is very unique-- it's not for everyone. Just my opinion though. You can see for yourself when you visit.
that being said.... I am still anxiously waiting for a response from duke...it's the only school I haven't heard from~