(UPDATED) As if it wasn't hellacious enough working customer support for Amazon.com on Easter, the online book store's reps must now explain why gay romances (and other books) are too "adult" to rank.

Straight romance like Jackie Collins and straight porn like this book of Playboy centerfolds is still ranked on Amazon.

But not the homosexul stuff: Gay romance publisher Mark Probst noticed hundreds of such books lost their rankings over the past two days, including Transgressions, about a 17th century liaison between a cavalry trooper and a farmer's son, and False Colors, about a 19th century naval lieutenant attracted to his commanding officer.

Probst wrote to Amazon through his publisher's account, and was told

In consideration of our entire customer base, we exclude "adult" material from appearing in some searches and best seller lists. Since these lists are generated using sales ranks, adult materials must also be excluded from that feature.

There is now an full-fledged Twitter shitstorm, naturally, and a new, snarky definition for the term "Amazon Rank," spreading virally. It's hard to imagine the Seattle-based retailer sticking by this controversial policy after naming a gay Brit's novel their "Book of the Year."

On the other hand, Amazon must be happy, on some level, to have finally expanded its customer base beyond the sophisticated techno elites, straight through into the American cultural backwaters where this sort of material is remotely offensive, somehow.

So probably the store will lump anything vaguely sexual, Jackie Collins and Playboy included, into a romance/erotica category, which will also be rank banned. And eventually the site will just throw in the towel and outsource its entire filtering operation to the cultural arbiters at Wal-Mart. Why not?

UPDATE: Author Daniel Harris wrote in to add some examples of non-romance books that have been banned from Amazon's rankings:

Three of my four books have been stripped of their ranking: Rise and Fall of Gay Culture (a gay history book but with chapters on pornography and S/M), A Memoir of No One in Particular (one chapter discusses my life), and Diary of a Drag Queen. Only my one "secular" book, Cute, Quaint, Hungry, and Romantic: The Aesthetics of Consumerism, retains the right to be ranked.

And Craig Seymour, whose gay stripper memoir you may remember for its mention of blogger Matt Drudge, blogs that his bio was banned from rankings back in February, even though Diablo Cody's straight stripper memoir wasn't. The good news is his ranking was eventually restored. The bad news is he noticed the memoirs of two gay porn stars were rank-banned while straight porn stars retained their rankings.