Busy is subjective, but having flown out on a Saturday afternoon in mid-September a couple of times, all seats in the departure area are taken and movement is impeded by the number of people standing. That, in my estimation, qualifies as busy, although I have certainly seen worse and I can easily imagine PJIA being worse when there are more flights.
When we flew on Tuesday, one could have bowled in the same area and not worried about hitting anyone. That was quite nice.