Location was important some years ago, but I think it's less and less relevant now. I think you can create amazing technology anywhere (in Latin America, in Europe, in Asia etc.)

Skype is a great example of this: they created a billion dollar company in Europe; and most of the development was done in Estonia (a country of about 1.3 million people, much less than most bigger cities).

Asia, especially Taiwan and South Korea, have some amazing examples as well (like HTC, Samsung, Asus etc.)