I ordered the book from Amazon (as opposed to a 3rd-party seller), and was told the book would ship in 4-6 weeks. 5 weeks later, I get E-mail from Amazon saying that the new expected delivery date will be 4 weeks later.
The first time this happened, I canceled my order and went looking for a faster means to get the book. Prices seem to jump around a lot, so I delayed, and ended up ordering again from Amazon. Surprise! My 4-6 week delivery date has just been pushed back another 4 weeks.
Something to keep in mind if you decide to order from Amazon instead of a reseller.