Now I live in the outskirts of Portland, in a place with modern suburbs grown up around a quaint old town. Sidewalks are everywhere. I take walks all the time, and I see other people out for walks daily.
It's seems like common sense that urban and neighborhood design can have a huge impact on the livability of an area, but a lot of the suburbs created in the US abandoned the sidewalk to save a few bucks and cram more houses per acre. I don't know if the tide has turned, but I'd never live in a neighborhood without sidewalks again.
Home buying tip: Look for a neighborhood with a strip of grass between the sidewalk and the street. It's a small detail that has a big impact on "neighborhood" feel.