Good for Google, for fighting the good fight and making "books" available online.
Sure, most people thought it was a good "IDEA", but were too busy trying to think of a way to make money on it. Google finds another, maybe "better" way.
Put it out there, and the audience (do not say market), will find you, IF it's worth it.
Want to know where the AUDIENCE is? Take a glimpse at what Teenage Japanese Girls are doing. They're reading books, (a sentence at a time), on their cell phones.
I've started reading a mini-book (Online), on using Python for working on the 3D Graphics program called Blender. One Linux Desktop for the Book another Linux Desktop for the Blender Program.