I’m sure we’ll start to see much more details on sales and revenues over the next few weeks but this is very interesting, at least to me!
With its actual-sales-generating bookstore, Google is now in the position where they don’t have to rely on links to Amazon (or Abebooks, or Bookfinder, or even Alibris/B&N) for revenue anymore. As a retailer, Google makes money just being a better, more reliable and consistent source for books than Amazon has become, one that can be stocked with your inventory in a snap via the simple .pdf or .epub files that every publisher has (or should have).
The new global catalog for books, if you will.
Eoin Purcell's Blog 