I didn't get an interview with Emory till pretty late, I think late November. I had been expecting to get an interview with them, so when I hadn't heard, I called, and they actually hadn't reviewed my application yet (yeah, what the hell...? I submitted it in early September). I got an interview a few days after I made the call.
I didn't get an interview with NYU until mid-December. No explanation for what that means.....Maybe my application was overlooked again, or maybe I just didn't make the first cut.
Moral of the story: call any programs that you haven't heard from yet. They might have overlooked your application or some other bull$#!t, and you really owe it to yourself to find out.