While I'm on the subject of transit, I wanted to reference a post from Matthew Yglesias highlighting the benefits of living in transit-friendly areas. The post is basically the following graph showing that people living in transit friendly areas spend less on housing and transportation combined:
I have discussed this previously with the Affordability Index map, which showed geographically for Atlanta what these graphs show. I feel like I've seen the above pie charts previously, but I can't remember where.
All this talk of density reminds me of an exchange with a class mate yesterday. He lives in Cobb County (I think), and came into town to meet with me for a class project. He was pretty surprised by the density of Virginia-Highlands. He asked me, "How do you live here??"
I forget sometimes how foreign my way of life must be to some folks.