Just to add a little more insight to what alphaRx said, the interview is pretty important imo. I heard they use it to kind of match students with their program. Most students applying have similar statistics and taking the best does not mean picking those with the best score. I think the interviewee's personality helps them differenetiate the applicants more. The questionairre is important because it shows them how well you can write and express who you are, at the same time it also allows them to get in more questions (during my interview we ran over time, and an adviser had to stop us).
I agree with alphaRx, read you questionnaire before the interview to remember what you wrote, in case they ask questions about it. My interviewer refereneced my questionairre but mainly asked me other questions.
Also, I think it is important to know and have questions about other things than yourself. I know during my interview I asked him as many questions as he asked me. We talked about the stimulus plan, universal healthcare, the effects of Medicare Plan D on small pharmacies, what UHCOP can offer me, and how Ike affected the school.
For me, I thought it was helpful to show that I wasn't only learning about the pre-reqs for pharm school, but that I was thinking about other things as well.