I remember when I purchased my radar and took it out to the courts. Most people, as has been said in this thread already, over-estimated their serves. Nothing has changed since, and I now live at a tennis club with 23 courts and players that range from weekend warrior to lower-level pros (male and female). From pre-teen to players in their 70's.
Most players, from what I recall back then, hit mostly in the 70-80 mph range, and this was with no pressure, and not worrying about placement. Majority of the serves didn't even land in the box. Only a few hit over 90.
As for the woman debate, I have never recorded a woman hit 100+ in the rec level. Not saying there are women out there who can't do it.