semcourses (March 1, 2008 at 10:05 pm)

It is true that one should only write a book on a subject that they know something about (and have actually done, as in the E-Bay example). But one also needs to make sure that other people are interested in (and willing to spend money) on that subject. How to travel with kids is something that people are willing to spend money on because it solves a problem they have - that's why it succeeded.You made this point in another video -- I just thought it should be restated here.