More related to Piketty's book (if you need more)
Arnold Kling, "Brad DeLong is Uncharitable to Piketty’s Critics".
Andrew Lilico, "Inequality isn't a problem: it's a driver of progress".
Tyler Cowen, "The wisdom of Scott Sumner".
Stefan Homburg, "Critical Remarks on Piketty’s ‘Capital in the Twenty-first Century’" (via Tyler Cowen).
Finally, for fun: "The nine stages of the Piketty bubble".