The US has approx 9x overall GDP as India, despite approx .25 the population, for 36x the spending power on a dollar basis. On a PPP basis per capita, its still 9x. In the very long run I'd certainly not bet against that GDP difference getting down to near 4x, but thats certainly multiple lifetimes away in terms of Social Networks

You don't seem to understand what exponential growth rate is like, just look at last 20 years of growth and the difference that was overcome by both China and India against US.