iOS 6 brings a multitude of novelties for users and unfortunately not many of them are available in all countries around the world. To help users discover more quickly which functions are available for their country, Apple has made a special page that lists the most important functions of iOS 6, as well as the availability in that country. Notice in the image that Apple has divided everything into 5 categories: Maps, Siri, iTunes Store, Dictation and App Store, these are most likely the only functions that suffer limitations.
Apple page you can find it here, I recommend you to visit it and click on each option separately to find out what it offers you.
