During the interview they were very clear that they are conservative about giving early acceptances to early interviewees, so that they have enough spots for people who are interviewing later. So yes it is rolling, but the bulk of acceptances won't be given until much later in the cycle.
That being said, there will be a few acceptances going out starting next week at the earliest, and that means that there will be fewer spots by the time you'd interview in Dec/Jan. I would say it would put you at only a slight disadvantage but it's unlikely to ruin your chances overall.