I just came across this article a few minutes ago and remembered your question. In one city in Sweden they're just giving people who agree to not drive for three days a week a free bike and a "bike coach" to help them figure out how to get around the city by bike. http://www.takepart.com/article/2014/05/19/sweden-serious-about-reducing-pollution-giving-people-bike-coaches
Barring this, I can't say enough about the value of good infrastructure in making it feel safe enough to ride in dense cities. When riding through the Northeast a couple of summers ago I saw a number of different ways of handling this (or completely avoiding putting infrastructure in) and found Montreal to be one of my favourite cities. Some places had physically separated lanes on very busy streets and the effect was noticeable. Even as the traffic zoomed by at 60-70 km/hr on one side, parents rode with their very young kids on their own bikes in the lane.