My town has a population of about 500,000. It is very hilly and there is basically no biking infrastructure, except for a few bike parkings downtown. ("A few" = count them on a hand and a half)
A good number of people commute by bike; mostly middle-to-lower class workers, and it pains me to see them not know the "proper" technique of following traffic direction, stopping at lights, not riding on sidewalks... but they get by. I've helped a couple with bike trouble on their way; sadly most seem to go on pretty decrepit bikes.
Then there are the "proper" ones, on well-maintained bikes, wearing helmets, etc., and they are invariably connected to the local biking groups. It's kind of disconcerting to see that "educated" bikers are the ones with enough money/time to dedicate to their biking. I guess I'm in this camp.
Things are definitely changing here, though. Drivers *are* getting used to seeing people on bikes riding properly on the streets.