I'm replying pretty late but FWIW I'm using book pages for our Graduate Mentoring Handbook: http://www.unl.edu/mentoring
I chose book pages for this because it was originally a print publication and it still seemed appropriate and useful to enable people to read through all its pages sequentially (and more easily than a non-book site would allow). The "standard" right-side book navigation (blue head, grey body, yellow highlight) always seems weird to me so I don't have it in this site, but I have the page sequence set up redundantly in the book structure (visible along the bottom) and the main menu nav (along the top) for the best of both worlds. I probably wouldn't have used book pages if this "book" wasn't its own CMS site.
And yeah: copy, paste... copy, paste... copy, paste... that's my CMS mantra so far.