Apple currently includes these cities on its list of locations that support the detailed city experience in Maps:
Atlanta, GA
Berlin, Germany
Boston, MA
Chicago, IL
Hamburg, Germany
Las Vegas, NV
London, United Kingdom
Los Angeles, CA
Melbourne, Australia
Miami, FL
Montréal, Canada
Munich, Germany
New York, NY
Paris, France
Philadelphia, PA
San Diego, CA
San Francisco Bay Area, CA
Seattle, WA
Sydney, Australia
Toronto, Canada
Vancouver, Canada
Washington, DC
However, it appears that at least two additional cities have gone live. One confirmed location is Houston, Texas, where Apple Maps now includes a rich 3D with custom-designed views including NRG Stadium, Minute Maid Park, Toyota Center, and Shell Energy Stadium. Apple has also introduced the detailed city experience feature to Dallas, Texas.