Does the interview matter to the admission decision?

<p>I've just had an interview with an alumnus of Princeton in the Starbucks. I can't believe Princeton offers me the opportunity because I'm in a rather small city in China. The interviewer is pretty nice and I like her very much.
We chatted about one and a half hours (not one hour as planned). The interview was all about my interests and hobbies, my high school experience and activities, and of course, her life in Princeton. I didn't have many questions to ask about Princeton, and what I actually asked was what she couldn't answer, because she's not one of the admission officer. And I'm pretty sure she didn't have much info about my application because I just sent all my applicaiton materials this early December (and I got the chance to be interviewed right after I submitted my application. This is amazing).
We didn't refer to any of my standardized tests scores, and I don't think the scores will help much. But I'm wondering whether the interview matters much? The interview was carried out smoothly and relaxingly, but she didn't comment anything about me and this interview at last. She just wished me good luck. Is this a bad news (I have heard that some applicants gained compliments after the interview)?</p>

<p>P.S. The major I want to study is exactly the major she studies when she was in Princeton. So we have much in common and talked a lot about the courses and professors. It's a pleasant interview after all, except some of my awkward grammer mistakes.</p>