Very interesting and eye opening read about the critics and the orientalist research around the Quran, its origin, context and language. It needs some familiarity with the text or at least the history of the Quran, and for that I recommend the book : The Emergence of Islam by Gabriel Said Reynolds.
The book is in 3 parts. The first ("Linguistic and historical evidence") is rather erudite and really didn't mean a lot to someone like me, who isn't conversant with semitic languages.
The second part, "The religious context of the late antique near east", was for me the most interesting. In particular, I was interested to read about "The Alexander Legend" which I'd never heard of. Apparently it was circulating widely in the eastern empire in hte 7th century CE and claims that Alexander the Great prophesied invasions from the north as part of the end-times. The author of this chapter reckons that it was written to bolster the Emperor Heraclius (never heard of him either!) by making out that the empire and the emperor was part of God's plan for the salvation of the world from the beginning. That's a really interesting insight into the way that Christianity was transformed from a subversive movement proesting against the empire to one that was used to support it. Another fascinating thing that I learned from this book is that one of the stories about Jesus' birth, which appears in both apocryphal gospels and the Qur'an, bears an uncanny resemblance to accounts of the birth of Apollo in Greek mythology.
And then the 3rd part is about Muslim exegesis of the Qur'an. it was interesting to see how this compares with modern western Qur'anic study.