Delacorte to Issue Unpublished Vonnegut Stories

From Publisher's Lunch:

Delacorte Press has assembled a collection of previously unpublished short stories by the late Kurt Vonnegut, which will include illustrations by the author, for publication in November 2009. The publisher has plans for a second collection of unpublished Vonnegut "writings" and a book of correspondence to and from the author. They also have acquired a follow-up memoir by the author's son, pediatrician Mark Vonnegut.

Bantam Dell editor-in-chief Nita Taublib and editor Kerri Buckley are credited in the announcement as having "put the collection together, often comparing and contrasting many annotated drafts of individual stories."

What are "writings?"