So for those who are interested, Robert just tweeted that The Walking Dead: Descent will hit bookshelves on 10/14. Per Amazon:
"Written by Jay Bonansinga, based on the original series created by Robert Kirkman, The Walking Dead: Descent follows the events of The Fall of the Governor, and Lilly Caul’s struggles to rebuild Woodbury after the Governor’s shocking demise."
Here's a link to the site Kirkman tweeted it has the first chapter available to read and some other stuff: