Amazon is not a member of the AAP.
(Neither is BAEN.)
Melville house is. (Snicker)
The BPHs (except S&S) are members, with individual imprints listed separately. Here's a listing of the trade book membership:
http://publishers.org/members/trade/
It is mostly old-school tradpubs, although Rosetta Books is listed. Not Open Road. Interestingly, Samhain is listed separately from Skyhorse...
Kensington is in. So is Wiley.
Given that list, the numbers look to be dominated by BPH results.
Curious that the only American BPH is not listed as a member of the American Association of Publishers.
