Distribution of wealth

I watched this video some weeks ago and couldn't put it out of my mind, was it the slick infographics or the underlying message? The video was about the distribution of wealth in America, highlighting both the inequality and the difference between our perception of inequality and the actual numbers.

It would be interesting to do this on a global scale. History tells us that inequality in the distribution of wealth leads to social instability. Are we heading for a situation when the 99% have had enough?