First off, I've seen some of the new software changes on the wiki, and they look great. As promised, I got my first book today, and I'm racing through it to come up with feedback for the PediaPress people. I have lots and lots of feedback already, most of it is not urgent or anything and some of it is going to be difficult to implement because it's sort of wikibooks-specific. Having a robust set of configuration options that can be set on the wiki would help alleviate a lot of these things without having to tie the extension to any single wiki.
1) On the table of contents, it says "Articles", when that word really doesn't mean anything for books. The first heading that says "Articles" should either be changed to the name of the book or should be removed entirely. Actually, you could probably read the value from [[MediaWiki:Article]] to make this solution portable. 2) Subpages shouldn't be prepended with the name of the book. For instance, the chapter should just be titled "CHAPTERNAME", not "BOOKNAME/CHAPTERNAME". Maybe we could have a way to override the displayed name of a chapter, which would make good sense for books where technical difficulties prevent the name from being displayed properly on the wiki. 3) On page "ii" it should probably contain the name of the wiki where the PDF was generated, and a link. Maybe also some kind of note that the "authors" are volunteers at the project, and that the name on the front of the book is an editor, not the "author" of it. 4) On the cover, the editors name should be marked with "edited by" or "Editor." or something so people know it isn't an author. On Page "i", it should say "Written by the volunteers at project X, edited by Y". Or something like that. 5) I like the way external hyperlinks are put into footnotes. Maybe we could have something like a special <footnote> tag, or a <div class="footnote"> or something that would allow writers to put certain notes in the page footer. This would be a great substitution for some of the messagebox templates that act like footnotes on the wiki. 6) Math formulas are generally very well rendered and handled, although integrals, limits and summations seem to be a bit cramped. 7) "articles" should each begin on a new page (I'm using the word "article" here so as not to be confused with the collections concepts of "chapter" and "page"). 8) Chapter headings should probably be on their own page, not just as a bigger heading before the next chapter heading. 9) I would love it if authors could specify some kind of "print name", such as in their preferences. That way people could be recognized by their real names if they choose, instead of by their on-wiki screennames. 10) Some images look very pixelated and fuzzy. What kind of compression is used? Can it be improved? 11) I'm sort of surprised that PediaPress doesn't post some kind of disclaimer here somewhere. Like "PediaPress and it's affiliates aren't responsible for the content of this book...". I'm even thinking that [[Wikibooks:General Disclaimer]] should become a permanent part of these books (But I want to see what people like Mike Godwin say about it first before I go on a crusade about it).
This is about it for now. Most of my other nitpicks have to do with formatting issues that we can fix by overriding templates, so I won't mention them here.
--Andrew Whitworth