Several sites (lehmanns for example) have the front cover online. I can see Ryan McGinley on it ("The Kids Were Alright"), Jacob Sobol Aue's "Sabine", two of the protest books presented in Paris last week.

To be released next year, around March/April - the rumour goes...

The third and final volume in Phaidon’s acclaimed Photobook series, hailed as ‘the most important contribution to the field since modern histories of photography began to appear in the early 20th century’ (photo-eye). This comprehensive study of the contemporary photobook brings the history of the genre fully up to date, highlighting over 200 books dating from World War II to the present day. Photographer Martin Parr and co-author Gerry Badger offer a fresh approach to photographic history, focusing on the development of photography in its published form and covering key genres such as conflict, memory, society, place and desire .

Thanks to Ben Krewinkel for the info!

And here you can find some of the books included in Vol. I and/or Vol. II