CNN article about the pros and cons of streetcars begs a huge question in its headline ("Can streetcars save America's cities?" assumes that America's cities are all dying or in decline), and omits any mention of Philadelphia, where multiple trolley lines began operating in the 1890s, and where the system has been running its subway-surface lines continuously since the tunnel between City Hall and West Philadelphia was completed in 1906. The Victorian rowhouses that comprise much of West Philly were constructed in this era, when the neighborhoods were built up as some of the first "bedroom communities" in the U.S. Now they're federally recognized as the West Philadelphia Streetcar Suburb Historic District.
Dig an interesting annotated history of the 34 trolley at the website of Studio 34, a yoga and wellness center on the Baltimore Avenue line.
Of course, many of Philadelphia's streetcars have been replaced by buses since the olden days -- the #23 bus is a huge example: though its rails are still in the pavement and its catenary wire is still overhead, the trolley route was was changed to bus service in 1992. But then again, SEPTA put "heritage" streetcars back on Girard Avenue's route 15 in 2005, after they'd given it the Route 23 treatment.
Philadelphia's subway-surface lines provide one of the easiest, quickest routes to get from Center City to multiple points in West Philadelphia: the hospitals (CHOP, UPenn, the VA, Presbyterian, and Penn's veterinary hospital), movie houses, Penn/Drexel/USciences, Clark Park, and any number of interesting restaurants, cafés, and gastropubs. Go a little farther out and you can get to Bartram's Garden; a few historic cemeteries; drug territories patrolled by thugs on ATVs; and Darby, birthplace of W.C. Fields. And that's not even mentioning the interurban lines: the 101 and 102 trolleys serving the towns of Media and Sharon Hill, and the 100 light rail serving Norristown. These vehicles carry tens of thousands of people around southeastern Pennsylvania daily (PDF). While a lot of Philadelphia's streetcar service was replaced long ago by diesel and now hybrid-diesel buses, I think it's a significant omission to leave out Philly's heavily used trolleys in a national news article about streetcars.