I read about this pretty cool opportunity on Mark's blog. Basically you apply to this site and you can request books from the select list they provide. You then read the book, provide a review of the book on your site and on a consumer site, such as Amazon, and you then get to keep the book. Once the two reviews are posted you can request your next book.
So, I signed up and was approved. Today I got to choose from a selection of only about 7 books (two of which were children's books though). I reluctantly selected the Lynne Spears book...although I admit I am a little bit curious about what goes on in that family.
Anyway, I am now awaiting my book. I think the next time I may request a children's book. I figured it is a great way to get free books, not to mention being exposed to books I might otherwise have overlooked.