Can you trust Amazon?

Amazon just came out with their Best Books of 2009 List. Aside from the fact that it's only November and there are two months of books to be read the list seems to be a little questionable.

Where are the women authors?

Just kidding. The problem I found with the list is that 7 of the books came out within the last 3 months (Sept,Oct,Nov) with 1 in August and another in June. Aside from Catherynne Valente's excellent Palimpsest (February), the vast majority of the books came out in the last few months.

While it's certainly possible that all of the best books came out in the recent months and I have no reason to doubt any individual book on the list as I haven't read them all, I find that to be coincendentally advantageous for Amazon. After all, chances are someone is going to be more interested in a new book they haven't heard of before rather than one they may have seen and passed on earlier in the year or one they already read.

And it's not just SFF. If you look at the distribution of Amazon's entire Top 100 books list. There are 31 books (31%) that have been released in the past two months (16.6%) with 1/5th of all books on the list coming from September. While this isn't as horrible as the SFF distribution I believe it's still statistically significant.

So what's going on? Picking 10 good books is easy. You could easily take 50 books for a Top 10 list accross the genre and have no clear argument for selecting or not selecting any individual book of the lot. So why did Amazon pick these 10? If you choose a bunch of old books or 1 book per month, theres a higher probability that readers have heard of these books and already read them. For example, a book that's been out since January will have had 10 months of shelf time to get through someone's reading list, particularly if they have the quality writing and critical acclaim that comes with making these types of list. Translation: No New Sales.

However, if you load the list with new books, chances are that people won't have had the opportunity to read them. I can read the best book each month but if all 10 books come out in October, chances are I haven't caught up yet, even if I am aware of all of the books. If I'm trying to read the good books, I might find myself clicking the add to shopping cart button a few times.

It's also certainly possibly that the recent books were the most fresh in the minds of those people writing this list. But if they really didn't do their homework and look at the full years worth of books (instead just picking the 10 good books they read recently), how worthwhile is this list? Is it fair to the authors who published their fantastic books earlier in the year?

There's also coincidence which while possible, doesn't seem likely. Do publishing companies try and put out their best books during September? Is there a publishing pregnancy period where authors get most of their writing done during the winter (or NaNoWriMo!) and they finally hit stores 7-10 months later? Are their simply more books in September? I don't know.

In my mind there are 3 options:

1) Coincidence/Publishing Schedule (Improbable but not impossible)
2) The Editors have the most recent books they read fresh in their minds (Possible but suggests that the editors didn't put in their due diligence)
3) Amazon wants eyes on the newest books so that people will buy books rather than simply seeing books listed that they have already read. (Borderline unethical)

So what is it? Is Amazon unlucky, lazy, or just plain evil?