When the iPhone 5 ships on September 21, it will include iOS 6 and all of the features the new OS version offers -- assuming you're in the United States. Since iOS 6's features are limited depending on what country you're in, Apple put together a Web page detailing where options like 3D Building view in Maps, as well as Turn-by-Turn navigation, are available.
iOS 6 Features: Not Available Everywhere
Apple broke down the feature list into categories: Maps, Siri, iTunes Store, Dictation, and App Store.
Standard maps, for example, are available in a long list of countries. The list for Traffic maps, however, is substantially shorter, and 3D Buildings view is available only in the U.S.
Siri's Sports, Local Search, Twitter and Facebook, Movies, and Restaurant features are limited to only a handful of countries, too.
As Apple signs more content deals outside of the U.S. the number of countries on the list will likely grow, but for now it's worth checking to see which features aren't available in your area.