I just got an email invitation to interview this upcoming friday (the 28th) from Pacific University. My friend interviewed on the 22nd and she said everyone was dressed very professionally, although the faculty was dressed a little more casual-professional. I'm not sure what kinds of questions they asked but I plan on talking to those who've already completed the interview.
For the interview on Friday, there is apparently a lunch with faculty and current students, a tour, and then the interviews which are 2 to 1 and can include SLP's from the community. One thing they asked my friend was what book, if applicable, she had read recently…
I'm sure there will be more typical questions but also questions that really help them to get to know you.