Joel was coming out with a new book and his old site was too tied to his first book. He needed a new look and one that could easily accomodate future books also. In Pub Site it was easy to create a color scheme to look good with both books and be easy to adjust to accomodate any new books.
Pub Site's "Magic Slider" let's you change your entire color scheme at once where the colors will still match and compliment one another. You can also change each color individually to create an unlimted number of combinations.
Joel also wanted to feature his two books on the home page along with their two book trailers. He was able to do that using one of the home page layouts offered in Pub Site.