Hey Buddy,
I am a third year at SCO. Congrats on the interview. Mine has been a few years ago, but I can tell you that, for the most part, the interviewers are very nice. One thing that might be helpful is for you to ask some questions, like 'where did you go to school?', 'why did YOU choose optometry?', 'what do you think is the best thing about SCO?', 'what is the latest development in optometric research?'...sappy stuff like that. Not that you care, just so that you can show some engagement other than the fact that you really want to get accepted...they love stuff like that! In other words, be enthusiastic, but don't come across as a spaz either.
Good luck, no worries, just be yourself! Tell them I sent ya! 🙂