Amazon's rankings are based on the books that they sell through their
on-line store.  As described in the previously-mentioned New Yorker article
(it _was_ the New Yorker, within the past few months), rankings are
compiled daily (and, if you're in the top 50,000, hourly).  My recently
published _MEDLINE: A Guide to Effective Searching_ was running steadily
around 53,000 until it got some press over the weekend, when it briefly
shot up to 6,554.  Then it dropped back to around 43,000.  Then a couple of
books got sold over an hour period and it shot up to around 1600
(outselling _War and Peace_ for an hour), only to drop back to 33,000.
During this flurry of activity, not a single copy got sold at
barnesandnoble.com, even though they were discounting the book.  Also,
because my book was recenlty published, it's not available in most college
bookstores.  So Amazon ratings have a very circumscribed meaning.

The most important thing is that alcohol-related books remain in print, and
if possible, be available at places like Amazon.

P.S. If you are looking for alcohol history in MEDLINE, use the Medical
Subject Heading "alcohol drinking" with the subheading "history" applied to
it (eg, "alcohol drinking/history), or use the Medical Subject Heading
"alcoholism" the same way (eg, "alcoholism/history").  Interfaces vary, but
all of them allow you to do this.  My book is not about alcohol history;
I'm happy to receive private e-mail queries about MEDLINE from ATHG members
doing alcohol searches.  Brian