At UW you generally have 3 interviewers: Good Cop/Bad Cop and someone to mediate the two (I think the mediator is the starred interviewer when you get your packet on interview day). You can only hope that the interviewer who is supposed to root for you will be vocal... unfortunately, for me it was the opposite and it was the antagonistic interviewer who asked most of the questions.
You will probably be asked Ethics questions... at least it's more likely here than at any other school. I, too, prepared using the UW Bioethics website, the NYTimes online health/science articles, and reading interviewfeedback. I was asked what I would do if I was a hospital administrator and a tobacco company offered me $10 mil for my hospital if I would agree to put cigarettes in every doctor's office, waiting rooms, etc. The interviewer than led me down a line of questioning ("Then what would you do?" "Then what?") until the topic and I were both completely exhausted. I was also asked about the Oregon Health Plan. I was also asked questions about current events ("Who's the Speaker of the House?" - though this is DEFINITELY more specific than most of the questions will be). Generally, I think they're just trying to get a sense of how you reason things out, and want you to be able to back up your ideas.
And I ALSO agree that UW does not feel like it needs to sell itself on the interview day -- they figure that most people who get in will come. This really pi$$ed me off because I felt like there was very little give & take, and not much opportunity to figure out whether UW would be a good match. However, I'm now a first year here and I have to say that things are a lot better than I feared. The administration does care about student curriculum and happiness, and they're willing to work with us. It's better, but it's still not as hands-on as it would be at some other schools.