This isn't set in stone, just server-space.
Here is my "great chain of being" for levels of textual complexity. Words in (parenthesis) are examples.
1. pure reference (dictionary)
2. structured non-fiction (small text books like "Natural Brilliance")
3. unstructured non-fiction
4a. biography
4b. structured fiction ("Pilgrim's Progress")
5. Essay collections
6. Unstructured fiction (novels without vauge chapter headings, "Ender's Game")
7. Short-story anthologies
I split #4 into two sections because I find PhotoReading a biography is about the same as PhotoReading structured fiction. Perhaps Pilgrim's Progress isn't the best example, as the author's margin-notes make the job of previewing and specific-activation more-than-easy. It is as if the book was designed with PhotoReaders in mind.
My own personal prejudice is against <I>reading</I> plays, but they would probably fall somewhere around 3.14 on this scale, as they're mostly dialog and direction with little description. The actors and director are left to interpret much of the details.
