Many rightly wonder about mis-measurement of productivity as new products become available and quality improves. Gordon is compelling in arguing that productivity growth is indeed significantly underestimated. He is also more persuasive than I expected in arguing that, if anything, this understatement was greater decades ago than it has been recently. In part this is because there were more of these transformational changes that are inherently hard to assimilate in standard frameworks. In part it is because the statisticians do a much better job than they once did of taking account of quality change.
The question of how to square developments that are large enough to have a major impact on wage and employment patterns with the paucity of measured productivity growth looms for future research.