This hold true for me, from my personal experience. I'm a shy person who doesn't easily talk to strangers. I talk to more neighbors where I currently live than I did in 9 years of living in the Washington, DC area. Looking back at all of those years living in apartments, I rarely talked to neighbors. When I moved to Arlington I talked to more people, but that was only because I was part of my complex's tenant's association.
Maybe it's not so much an urban-suburban split as it is a regional phenomenon. People are just friendlier to each other in the Midwest. I was thinking yesterday about my time in Washington, DC and how lonely I felt in that densely populated city.
Chuck -------------------------- Bread and Roses Web Design serving small businesses, non-profits, artists and activists http://www.breadandrosesweb.com/