You should have a separate forum for each book, with separate sub-forums for each chapter. Then people can discuss specific sections within each book. Rather than asking general questions about the topic, these forums would be to discuss issues that come up in reading the book itself. for instance, code that doesn't compile. Or maybe just code that generates an error because a newer version of a compiler now checks for additional things, not accounted for when the book was written. Or phrasing that is vague or inconsistent. More than just errata, this forum would be for readers to help other readers understand the book itself. In addition, the authors would receive more in-depth feedback as to their own writing skills.
You should link to these forums directly from the book's home page.
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