A new research paper determined that residential properties near transit stations in five major cities across the US maintained their values significantly better than properties outside of "transit sheds." The New Real Estate Mantra: Location Near Public Transportation (pdf), commissioned by the American Public Transit Association in partnership with the National Association of Realtors, examines the Chicago, Phoenix, Minneapolis-St. Paul, Boston, and San Francisco regions.

http://bettercities.net/article/transit-oriented-walkable-places-held-real-estate-values-better-19908