I enjoy making the overlays (thanks mostly to xRez and GIMP),
but I don't have any specific plans to make a book with them.
Some of them work on a computer screen a lot better than they would in a book -
the Sentinel West Face (10" x 31") and Ho Chi Minh Trail (6.5" x 30") overlays are very tall and narrow.
Easy to scroll up and down on the web, but they would have a very
reduced width in a book that would fit on a bookshelf.
(Kris Solem made this point earlier when I posted a huge photo overlay for some Voodoo Dome routes in the Needles - that amount of detail doesn't fit into a 6" x 9" guidebook; it might not fit into a coffee table book, either).
The current book is topos (black and white line drawings) and I'm trying not to get too distracted! :-)
But there will be some overlay photos for locating things.
It hasn't been decided yet if they will be in color, but it's getting cheaper to use color and I struggled to find things in the previous black and white overlays.
One possibility would be to put the overlays in a PDF or similar that could be viewed on a smartphone. Some people take their phones on climbs with PDFs to look stuff up if needed. "Just don't call me." :-) "Dang it, Clint, your overlay guess was way off and now we're stuck!!!"
Ed had a cool idea of some kind of overlays integrated with an xRez type zoom-in system. I.e. you select the route(s) you want overlaid, then zoom in to see more rock detail. The line width stays the same, so the line obscures less rock as you zoom in. Maybe a "coffee table" style screen?
"Armchair mountaineering" or "shadow climbing" (my old friend Dan Nguyen taught me that last term, like "shadow boxing").
Would be a money maker if you could find a cheap way of getting a big color coffee table Yo guide printed in the States or elsewhere (China!). Nice to make it a full multimedia production with continuously updated interactive links to topo pdfs and giant wall pics. Videos taken on the routes would be hot too. That way you could have all the advantages of a book and the advantages of Internet based information reinforcing one another.
To clarify my statement (woke up late with a headache!):
A big coffee-table text/graphics/image book linked to (and supported by) continuously updated online resources at a site with downloadable topos in pdf format and larger images of walls and areas too big for the printed medium all with gps coordinates you could access in the field from a smart phone. Of course, at home from a PC or Mac too.
A lot of big history and art books from publishers like Oxford University Press and eminent historians like Anthony Beevor are like that right now. More information and videos at the web site that didn't appear in the book.
Again, no easy project, but given current technology very do-able. Trip reports and topo updates too. The book could serve as a front for a sort of mini-Yosemite climbing industry. What about some funding from the AAC?
Also, lots of online videos linked to individual climbs to illustrate cruxes and belays. Even mo' work!