For those of you wondering whether to buy from Amazon or directly from O'Reilly, I heard from our Amazon sales rep that Amazon is temporarily out of stock, and is in fact showing as "not yet published." She wrote in email:
"Since I've heard from several of you regarding Programming Collective Intelligence and the status on Amazon, I thought I better send out a quick little note to explain the "glitch." As most of you have seen, Amazon's detail page for Programming Collective Intelligence is now showing as a pre-order but just last week it was "available." ... Here's what happened as it's been explained to me. Apparently, Programming Collective Intelligence ran out of stock as quickly as it was received in. Because it ran out of stock so close to the expected pub date, the system threw it back into a pre-order status."