One of the useful things about online bookstores such as Amazon is that they stock just about everything. Even if a book is no longer in print, they will put you in touch with a second-hand dealer who has a copy. Advocates of “long tail” marketing tend to claim that this means Amazon is good for market niches, because every book has the same access to the market.
Well that might be true, but Amazon also makes the whole world one big market, and it provides recommendations. What does that mean? It means that it encourages everyone to buy the same books, the same films, the same music, as everyone else. Tom Slee explains the mechanics of the process. There will doubtless be some who will nit-pick the experiment, and claim that disproves the findings, but as far as I’m concerned it sounds very logical. If you concentrate all transactions in a single market then you are bound to produce convergence of taste.
Of course this doesn’t mean that you can’t sell niche interests online. The ease of communication is still a good thing. But you won’t be able to rely on Amazon to do the selling for you.