Walkable neighborhoods are great on many levels. The latest news is that they help to preserve your brain.
I've lived in 9 neighborhoods in the past 9 years. Several of those have been very walkable neighborhoods, but some more than others of course. I've realized in my current one, one of the most walkable yet, that a nice, walkable neighborhood is a tremendous value that cannot be quantified by calculating the transportation and time savings. Well, I have known that for ages, but it has really been registering for me lately as I walk with my wife and baby daughter to one wonderful park ~3 minutes away, a huge park/forest ~5 minutes away, or a low-key but super useful shopping center ~4 minutes away. If I miss a day of walking around the neighborhood, or if I haven't yet been out as the mid-afternoon rolls around, I can feel something is just not right — with my body and with my head.
Still, this recent piece of news surprised me: a study from the University of Kansas has found that "neighborhoods that motivate walking can stave off cognitive decline in older adults." My guess is that such neighborhoods also help with the cognitive functions of not-so-elderly adults and children as well.