I live in Sudbury Ontario, about 4hrs drive north of Toronto. Generally, the temperatures in Sudbury average 5-7C below that of Toronto which is likely because of its size and proximity to Lake Ontario. Most mornings in the fall, I don't see a single bike commuter although I know of a couple who take a nearby route. I was in Toronto yesterday and amazed and somewhat overjoyed to see the number of bike commuters: I almost wanted to buy a bike just to join them. It seemed to me that the difference in numbers was more than just the climate and population, it seemed that it was more a part of the "culture" than here in Sudbury.
Although I didn't bike in today because I arrived home late last night and didn't have sufficient time to organize myself, I am going to continue to bike commute in as long as I can and start in the spring as early as I can and hopefully, encourage others to do the same.