Venita prides herself on being a "professional interviewer" or so she told me with an evil grin.
I'm sure the UF interview is intentionally made to be intimidating. I went into mine prepared to be "grilled" but what completely threw me off (and sent me off with my tail between my legs and a rejection letter) was how completely disinterested the interviewers seemed in me or my attempts at conversation. One had a cell phone go off twice, one STARED at the clock the entire time, and Dr. S told me "so, you don't really know why you want to be a dentist. In your heart, you don't know".
So I guess my best advice is don't get caught on your heels. They might be very pleasant or they might be flat-out mean. They could also seem completely apathetic and if you go in expecting one certain interview type you'll find yourself on the defensive very quickly. Just answer their questions the best way you know how and tell yourself through the whole thing that they're only partly listening to your answers -- they're really seeing how you react.
Hope that helps and doesn't freak you out any more.
Mack