I think you should have added a "on the due date" button to your poll because although few peoples' babies come right on time--I went into labor naturally at 1 am on my due date--my son was born the following day. I would count that as "pretty on time" but most of my friends having their first babies were late by at least a week and most were induced because of this.
My son was 12 weeks early, born at 28 weeks weighing 2lb 5oz. I am 38 weeks pregnant with my second and starting to get contractions this morning but not too bothered because she will be considered full term now.
wow, so far, there's a huge % that were more than a week early!! Mine was 4 days early. Thankfully!! I didn't want to wait much longer!! At the end of a pregnancy, every day seems like an eternity!!