I'm sure you've all heard of the "price war" on books taking place online. If you're a consumer, it's a great opportunity to buy a book cheap. For the price warriors it means publicity, and sales at a loss, but with perhaps future sales to make up for any losses.
What does it mean for a writer? It means a devaluation of the art of literature. The loss of publishing options. And, it may be a death knoll for up and coming writers.
If you haven't seen it, I direct you to a piece by William Petrocelli, in the Huffington Post.
For readers it may be the end of choice. Think about it--do you want Target and Walmart deciding what reading choices you'll have in the future?