Thanks to everyone for the very positive response about the upcoming Yesod book! There were various questions floating around the comments, Google+, Reddit, and email, so I just wanted to give as thorough a set of answers as I could.
- The book will be available in paperback and ebook format, supporting Mobi and ePub.
- For the ebook, you can get it directly from O'Reilly, which means you'll get updates. It will also be available from various other sources: Amazon, Nook store, iBookstore, Kobo, and more.
- I know Amazon says the book is 100 pages; that was just an initial guess from who knows when. The book is close to 300 pages.
- The book is being updated as we're making changes to Yesod. The goal is to release the book not long after Yesod 1.0. The book should cover that release.
- The current book on this site covers 0.9. There's a beta version that covers 0.10.
- Some people believe the book is imbued with magical powers, and can cure people of all ailments and turn lead into gold. That's absolutely ridiculous; lead can't be turned into gold.
If you have any other questions, let me know, I'll try to keep the post up-to-date with answers.