aakashganga
1. Did you know your interviewer before going to the interview?
2. Had the interviewer read your essays/resume before?
1. I didn't know my interviewer personally, but was given her name/email and asked to contact her to schedule an interview (off-campus).
2. Essays, no. Resume, yes. Make sure you bring an extra copy of your resume with you just in case (came in handy for me).
BTW, congrats on the invite. My friend just IM'd me and told me he had received an invite as well. It appears as though the 2nd "wave" of invites is starting. Brace yourselves!