I can confirm after an analisis of the .bin file that Amazon it's doing something to the update file before erase it, it embeds book files on the "sectors" of the update file.
I can see the following books on this .bin file:
The Blue Air Compressor - Stephen King
I, Robot - Doctorow, Cory
Night Shift - I Know What You Need - Stephen King
Got Fangs - Katie Maxwell
Gossip Girl Book 1 - Cecily Von Ziegesar
The Shadow Rising - Robert Jordan
This is something that i have not seen on any other update file, just the k2i update files.. strange (all the bin files recovered for k2i has this kind of protection)
BTW.. leodavilgen your friend has a nice taste on books, tell him to make me a friend on goodreads !! (
http://www.goodreads.com/bzImage).