This morning, Amazon revealed they have sold “millions” of Kindles in the last 73 days. That may be the most concrete sales figure the company has ever offered about the popular eReader.

Last week, Amazon gave Author Central writers free access to Nielsen BookScan’s weekly geographic sales figures for their print books. The move touched off another debate about transparency and sales figures. Below, we’ve collected thoughts from two authors on the topic.

Here’s why author Dave Cullen did check his sales figures: “Publishing is in the dark ages on market data. (And in involving their own artists.) Books are the only major pop culture market that doesn’t report real data to the public (popular bestseller lists are kinda-true, but offer no numbers whatsoever), and the only one where no organization captures close to 100% of sales.”

Read more