Wear whatever you feel most comfortable and confident in. If you think you look your best, you'll present yourself in the best way. If you feel akward in a skirt or worried about what people may think of a pantsuit, you'll be preoccupied by these thoughts and won't seem as confident as if you wore what you felt best in.
I went with a classic knee-length black dress with matching black suit jacket over it (from Ann Taylor I think). I interviewed for surgery, one of the more conservative specialties. My dress was classy and not too sexy, so I think it projected a good first impression. I do feel that I look more attractive in a dress suit than a pantsuit and I do believe that at least subliminally people are more likely to hire and attractive person than an unattractive person. Not fair, but true. So wear what you think you look best in because looks do count, fair or not.
BTW, none of the places I interviewed made us put on bunny suits and go into the OR, we just walked past the main desk, locker rooms, lounge areas and kinda peeked down the hall. So don't use this as a factor in your decision. Comfortable Shoes are key, I agree with that.
