I'll be reading Marcelo over the next few evenings.
The bookmap assignment was quite interesting. I didn't finish it, but I did enough of it that I can see the potential value of doing it and I might end up finishing it after the workshop.
My friend Kim has a great post on her blog about bookmaps. She has also made a wonderful video on How to Create a Bookmap. Check out both links; it's worth your time!