> Indeed, in 50-100 years, when China or India have caught up with the developed world in terms of GDP per capita, the potential entrepreneurial gains from being able to market to a Billion people at once will make US business fortunes look modest.

I don't know about India (but I'm sure it's a similar situation), but in China you have vastly different cultural groups across different regions. It's a large country. And I'm talking a larger cultural divide than "East Coast" vs "West Coast" in the USA.

I doubt that you'd be able to having a marketing campaign that included all 1 billion people... It might be viewed by close to a billion people, but you'd have to be targeting a smaller demographic.