"Reinventing Comics" by Scott McCloud is quite an interesting read. it's right above me at my desk now.
It's not the best comic in the world, b/c I felt he violate the #1 rule of visual media --> he narrates almost every frame. However, he has a visual accompaniment to explain his thoughts on subjects, and he is quite a deep thinker. A visionary. A dreamer.
Yeah, I liked the book... But it's a better read for the comic artist/writer/inventor than for anyone looking for entertaining diversion.