If you haven't already done so, this Friday I recommend checking out Amazon Charts. For a long time, Amazon has made available best seller lists in multiple categories that are updated hourly. (For instance, you can click and find the Top 100 Free Occult Kindle books or the Top 100 Paid Reference books.)
Amazon Charts, though, is something different. It lists the Top 20 books for the week in four categories. Most Read Fiction, Most Sold Fiction, Most Read Non-Fiction, and Most Sold Non-Fiction. The lists include audiobook, paperback, and ebook sales on Amazon.
These companion lists allow for comparisons between what people are buying and what they are reading.
Until Sunday, when I'll talk more about best seller lists–