LOL. I miss that handle. It feels good to be an exurban expatriate, living in self-imposed exile in the big city.
I would define exurb as "an area that serves the suburban role of being within the commutershed of the city, but which is rural in nature".
Exurbs are different from towns, even if that town serves a commuter role. A better term for places like Barrie, Stouffville, or Georgetown would be "commuter town". Towns are by definition urban in nature (not "extra-urban") and have a historical reason for existing other than as a bedroom community. Uxbridge could definitely go either way, but I would argue that for the past 25 years it has been a commuter town.
Caledon is a good example when looking at exurbs, as the entire township* is within commuting distance from either Toronto or the jobs in Vaughan, Brampton, or Mississauga. Exurb in this example would include purely rural areas, villages, and very small towns BUT Bolton and Valleywood would not be included as they are suburban in nature.
It seems that some people just feel the need to own somewhere between 2 and 100 acres even if they have no practical use for it. Don't ask me why.
*I know it's not a township, but I use this term to differentiate from the towns and villages within Caledon. Too many people think the "Town of Caledon" lies at the intersection of Hwys 10 and former 24.