Yes, "idiots" is a bad phrase, because it says something about the reader that is not strictly related to how the reader needs hand-holding; the target reader is a beginner at MODx but may have skills from elsewhere. The best thing is to have a basic overview of website development and programming in an early chapter to bring people up to speed (which would recommend other books for those who need more detail in that area).
Possible titles:
"Introducing MODx"
"MODx for Beginners"
"MODx for Newbies"
"A Beginner’s Guide To Creating Professional Websites With The MODx Content Management Framework"
Or the first one with the second as a subtitle. Or any mix and match. Really, it’s easier to come up with a title once it’s been decided what would be in the book and what would be in a second book.
The original poster mentions Safari - I don’t know what one has to do to get a book in that, I know it’s not just O’Reilly books. But having instant on-line access to a book, as well as there being a proper print copy, is quite useful so <a href="
http://www.lulu.com">Lulu</a> might be worthwhile.
I *would* be interested in helping such a project, and I definitely offer my services for sub-editing as David suggests, however I do have limits on my time.
As it stands, the best introduction to MODx is probably the sample content in 0.9.5 - it’s a significant leg-up. There are lots of bits of information out there, but there is no linear document bringing everything together - everything cross-references everything else.