A recent blog post by Yonah Freemark about All Aboard Florida is well worth the brief time you'll spend perusing the article. The conclusion is worth posting here:
Most U.S. regions are too sprawling, too auto-dominated, or too poor to expect this kind of transit-oriented development to occur simultaneously with new rail or bus links, particularly if that means that the transit agency has to take on some risk that a project will fail financially.
Ian Carlton is a transportation and land use expert specializing in transit-oriented development (TOD). He helps clients - including transit agencies, planning departments, and landowners - optimize real estate development around transit.
Special thanks to Burt Gregory at Mithun for permission to use the Portland Streetcar image above.