Print sales also increased, and that's amazing considering that the AAP has repeatedly reported that the publishing industry as a whole is down in terms of revenue.
But that's not the most interesting data. Sourcebooks also reported that sales via the Nook store also increased over Christmas, and in fact the Nook sales grew far more than the market as a whole. Clearly those annoying emails I reported on before Christmas had a positive effect on revenues.
BTW, I now that I've said stuff like this in the past, but the Nook growth that Sourcebooks saw over Christmas would not have been possible if this publisher had chosen to sign up with KDP Select. The above stats are a practical example of why exclusivity is rarely good idea.