Nathan Newman's got a very strong post on the primacy (or puzzling lack thereof) of housing issues on the progressive agenda. And he's right on it. Employees of all incomes and occupations know how little they like living in zip codes wholly unconnected to their workplaces just so they can afford a roof for their children. The commute, the lack of flexibility, the total disruption of everyday life -- it's crushing.
In addition, many of these folks are becoming Republicans, either in reaction to the urban areas that banished them or as simple result of becoming property owners. It shouldn't be that way, and speaking to the everyday hardships of their commute and conditions would, if nothing else, prove Democrats are on their side as much as the city's. Kevin Drum likes to say that the divide isn't red vs. blue, it's urban vs. rural. But it's more than that: it's urban vs. rural/suburban/exurban, it's urban vs. everyone else. Affordable, well-planned, high-density housing that would let families of moderate means live near their workplaces and thus reclaim their time speaks to the everyone else in the equation, and if Democrats piss off some urbanites who don't want development along the way, well, good then.