I was talking with one of my former advisors yesterday about how my application cycle is going, and he told me a story I thought I'd share with you guys. He helped another student a year or two ago get through this process. She was competitive, but there was nothing stellar about her application. Like most people, she was complete at her schools in August and early September, but heard absolutely nothing for months. Then in January she got 6 IIs in the span of a few weeks, and ended up getting accepted somewhere in March.
Of course, n=1. It won't be like that for most people, but it made me feel better about where my application is right now. The point is, even if you don't have an interview yet, I don't think you should be too worried. I think this is especially true considering the AMCAS delays this year.