Apple has announced that as of July 1 it will be discontinuing iBooks Author. While I am not surprised and felt iBooks Author had languished for many years, the early potential of this product seemed great. Apple never bothered to offer a reasonable way to port iBooks to other platforms. While superior to Kindle books in my opinion, it was never worth the effort to develop for iBooks only.
Apple intends to upgrade Pages as a way to create books for the iBooks store. Those wanting to sell through the store will still have an opportunity, but the books will still be limited to Apple devices. Sad.