Interviews vs Auditions

I have an interview for a job today. This is the first corporate job interview I have gone on in, I don't know, 6 to 8 years. In those years I have worked as a flight attendant as well as a design consultant for a small firm of 3.
I haven't been in a corporate environment since I was pregnant with my son. He's almost 8. Needless to say, jumping back into the saddle is a bit nervewracking and somewhat confusing.
I have been a print and commercial model for the last 20-some odd years as well. During this time I have been used to going on auditions, go-sees, cattle calls, so to speak. This I am used to. You take your book and/or card, you slate your name, you let them take a polaroid, you turn around, you walk out. There are usually 10-150 other people in line to do the same thing, for that one print job. 20% of the time, I get the callback. Nice! The other 80% of the time, I leave knowing, it just wasn't my day. No big deal.
When I was called for this interview today, I was told, "This is a preliminary interview - just the 'first' in the interview process". I was slotted at 4:35p. Hmmm Sounds quite a bit like an audition. 5-10 minutes to be seen, and in that brief time determined if I am viable material for the available position. I don't know what I could say in 5 minutes to determine my qualifications for this position, but it occurs to me that in 5 minutes I hope I at least look the part to get the callback.