Ghost of a flea pointed me to jeff black, berlin, who writes:
German researchers preparing “Qur’an: The Critical Edition”
This is a serious business. A team of researchers at the Berlin-Brandenburg Academy of Sciences is preparing to bring out the first installment of Corpus Coranicum – which purports to be nothing less than the first critically evaluated text of the Qur’an ever to be produced.
What this means is that the research team is in the process of analysing and transcribing some 12,000 slides of Qur’an mansucripts from the first six centuries of the text’s existence. Once that is complete, the way is open to producing a text that annotates and, presumably, provides some sort of exegesis on the differences found in the early manuscripts.
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The Potsdam-based team of Corpus Coranicum have so far concentrated on Suras 18 to 20, and are due to produce a first slice of the final product from that in the next few weeks. The whole book is meant to take until around 2025.
UPDATE: The English language site seems to be down but the Google cache contains the following, seemingly from an old update:
Welcome to the Corpus Coranicum
The project “Corpus Coranicum” contains two unworked fields of qur’anic studies: (1) the documentation of the qur’anic text in his handwritten as well as orally transmitted form and (2) a comprehensive commentary which elucidates the text within the framework of its historical process of development.
Because of the ambiguity of the early defective writing system of the Qur’anic manuscripts, a strict separation of the data on the one hand provided by manuscripts and on the other hand transmitted via the tradition of recitation is recommended. The documentation of the Qur’anic text will provide a documentation for both traditions and compare them afterwards.
The planned commentary focuses on a historical perspective, the Qur’an seen as a text which evolved through the period of more than twenty years, thereby getting formal and content-related differences through abrogation and re-definitions within the text. Furthermore, the commentary is based on an inclusion of the judeo-christian intertexts and looks at the Qur’an as a document of the Late Antiquity. “Corpus Coranicum” is in the early stage of its development; the first results are planned to be published online in 2009.
That shows a very sensible approach. You eat an elephant a little at a time. Rather than working on a Koran text as such, work on the early witnesses to the text, the physical remains, the unvocalised scripts, and find out what we actually have from that period and what it says.