shadowsjc
i went to an HBS prospective student event a few weeks ago.
prospective students: some wore suits, and some wore business casual.
actual students: very very casual. im talking jeans and tshirts casual. as such, the prospective students in suits kinda stuck out.
if you're interviewing, i'd say wear a suit. if youre just visiting, a dress shirt and slacks (no tie) would probably be ok
edit - i forgot i went to NYU this week as well for a tour. more than half of the people went in suits, which was overkill IMO. i wore a long sleeve tshirt and khakis, very few people wore jeans.
I don't think any of the students really care (as an ambassador, I really didn't look out for what people wore). As classes and stuff are arranged through admissions, you are always going to be better off in business casual.
What the students wear is not really relevant, save for working out whether you think the school is too uptight in general. Sure, they wear jeans and a t-shirt. When you have taken a vow of poverty to not earn for 2 years and pay fees, you earn the right to wear whatever the hell you like.