Also, this was posted on King’s board:
The moderator at S.K. message board gave details on the new D.T. book:
"Stephen has given me permission to pass along that he has an idea for a new Dark Tower book, the working title of which will be THE WIND THROUGH THE KEYHOLE. He has not yet started this book and anticipates that it will be a minimum of eight months before he is able to begin writing it."
Thanks to Steven Seebode and David Squyres