I recently became aware of Of Dice and Men, an upcoming book about D&D by the an old college friend of my wife. I haven't read it, but it looks like a lot of fun, and has excellent celebrity reader blurbs:
“David Ewalt writes about the world of fantasy role-playing junkies with intelligence, dexterity, and even wisdom. (I am unable to speak to his strength, constitution, or charisma.)”
(Ken Jennings, author of Maphead and Because I Said So!)
"The best book I've read since the Monster Manual."
(David X. Cohen, executive producer of Futurama)