The Economist does a quick dive into the issues raised by this piece and why they don't fundamentally change anything:
http://www.economist.com/blogs/freeexchange/2014/05/inequali...
> The fourth question is whether the book's conclusions are called into question by Mr Giles's analysis. If the work that has been presented by Mr Giles represents the full extent of the problems, then the answer is a definitive no, for three reasons. First, the book rests on much more than wealth-inequality figures. Second, the differences in the wealth-inequality figures are, with the exception of Britain, too minor to alter the picture. And third, as Mr Piketty notes in his response, Chapter 10 is not the only analysis of wealth inequality out there, and forthcoming work by other economists (some conclusions of which can be seen here) suggests that Mr Piketty's figures actually understate the true extent of growth in the concentration of wealth.
