- There exists functionality within Amazon's system to keep items from being found in various search results (like searches for best-selling or categories or keywords) based on certain metadata "qualities".
- Someone abused this functionality to put GLBT-themed works into the "non-findable" lists and thus render them invisible.
Making Light has a nice article on amazonfail, and their opinion and mine are similar.
Why would the Amazon system have such functionality?
It could be very useful for an individual customer to filter what gets displayed to them ("don't show me items about X" or "items similar to this one") or even for use with certain accounts ("if the user is under 18, don't show items that are adult"). Certain responses from customer service that people received pretty much say that the functionality exists.
Who abused the functionality? Either someone external to Amazon or someone internal to Amazon.
External would require a coordinated effort to apply the required "qualities" to works and have the application occur in what appears to be a small amount of time. There were works disappearing in small numbers earlier (in Feb/March), but this disappearance is fairly wide-spread.
I bet it's someone internal to Amazon. The timing (Easter weekend) and the scope (fairly wide spread) tell me it was a matter of someone "flipping a few switches" inside the system. Especially when, for some works one version of the work disappeared and one version didn't and the different was certain metadata tags about subject matter and/or categorization.
Dear Author has a very good article on this with some investigation results. LJ user tehdely has similar conclusions, but thinks it could be a different external source.
I expect (hope) Amazon to come out soon and say "it was some rogue employees who took advantage of features in Amazon's system to cause this to happen, and we're very very sorry and have taken steps to make sure it doesn't happen again". We'll see what happens.
No matter what, the situation is wrong. The first book in the results list of a "homosexuality" search, along with most of the books in the list, should *not* be a anti-homosexuality instruction manual. I'm certain they are not the best-selling books with that tag, nor the highest recommended (see the "Dear Author" post linked above for why these books would come up first).
Tell Amazon how you feel, via website or email. A purchasing boycott until they fix the situation is perfectly reasonable (and let Amazon know this is happening). Whether or not one wants to buy from Amazon again (once things are fixed), that's a personal decision.
But I don't think this is some new Amazon "policy". Amazon wants to sell things. Amazon has offered employee benefits to domestic partners for a while (check "Benefits" under "Careers at Amazon"). I believe Amazon has even been placed on lists of "GLBT-friendly workplaces" in the past (but I don't have the reference).
Someone used features in the Amazon system against GLBT-themed works. And, also, against Amazon. Once this all settles, we'll hopefully know the full details.
ETA: Here's a nice list of things you can do to show Amazon how you feel (from Okazu, via lilithsaintcrow).