I tend to PhotoFlip in the bookstore when I'm trying to decide whether or not to buy a book. I usually get a good sense of the book right away.
I have activated books in the bookstore.
I've also PhotoRead a bunch of books on a subject to help build a base of knowledge on the subject. I'll typically do more of a postview than an activation.
How much experience do you need? Don't know. Depends on too many factors.
