I applied to this position on my university career site. I received a call the next day from someone who explained what the position involved and what the company was like. I had my one-on-one interview on my campus a few weeks later.
The first thing the interviewer told me was that this interview wasn't going to be a typical interview where they ask about your strengths and weaknesses. The interviewer said it was going to be more of an informational thing and consisted of the her explaining the position and company and then asked me if I had any questions. I had lots of questions, so the majority of the interview was me asking questions and her answering them. The interview lasted about 20 minutes.
I received an email 5 days later saying that after their many interviews at three different universities, they found other students that had more previous professional experience and would not be offering me the position.
They are basically using the 1st interview to get a feel for your personality and motivation. The 2nd interview is the professional one.