Using econometric models that control for a number of possible concomitant trends, we found that sales [of video and music] did shift measurably into the tail.... Rather than bulking up, the tail is becoming much longer and flatter.Meanwhile, our research also showed that success is concentrated in ever fewer best-selling titles at the head of the distribution curve.... The importance of individual best sellers is not diminishing over time. It is growing.Wired's Chris Anderson, who authored The Long Tail, wrote that the research seemed sound (though personally I think that would be tough to tell unless you could see and understand the econometric models), but argued that the real issue is the definition of "head" and tail":
"Head" is the selection available in the largest bricks-and-mortar retailer in the market (that would be Wal-Mart in this case). "Tail" is everything else, most of which is only available online, where there is unlimited shelf space.In other words, by changing the definition of head and tail, you can end up with very different results.
I once headed product marketing at a direct marketer of programming and engineering products and presided over a collection of products that ran into the thousands. I noticed a pattern: the more products in a catalog, the better sales were. However, the additional products weren't necessarily the ones selling. Instead, we seemed like an authoritative place to get products, and more people tried there first. As management directed us to cut the number of catalog pages, sales took a hit, although they still huddled in the most popular products.
In marketing, perception is all. I think you'd see similar patterns at Amazon.com when it comes to book sales -- people go there because they can find what they want, and then statistically buy what you'd expect. So a long tail may increase "head" sales disproportionately. There's nothing wrong with that from the view of the business, but management had better know what is working and why.
The other point is simpler. Out on the tail, you could double or quadruple your sales and still make diddly squat. Sellers who have efficient infrastructure, not inventory, can benefit from the incremental income and margin. But the content creator may find that the long tail can quickly become a long chain to jerk.