Desert island books, as it were

So you've got a lot of time on your hands. Whatcha gonna read? Tom Ricks reports:

The three most popular books at Guantanamo's library for detainees reportedly are:

1. The Harry Potter novels
2. Miguel Cervantes's Don Quixote
3. Barack Obama's Dreams From My Father

I don't know what this means.

It would be helpful to have a list of the books available for comparison's sake. And I presume the absence of the Qur'an is due to its being available to prisoners in their cells.

(Why is it, btw, that we so often fall into calling the prisoners "detainees"? Is Gitmo not a prison? Is the implication that one becomes a prisoner only after being convicted and sentenced?)