I've gotten a bit behind on posting the "Author's Notes" here, so I'll try to speed through a bunch of them this afternoon. First up are Brian Herbert and Kevin J. Anderson on Hunters of Dune: 

Frank Herbert's Dune Chronicles span five thousand years. Herbert's last novel, Chapterhouse: Dune, published shortly before his death, ends on a cliffhanger with our characters trapped aboard a ship, fleeing across uncharted space from an unnamed Enemy. Millions of fans have waited more than twenty years for the conclusion to that story.
 
A decade ago, when we decided to continue the Dune series, we knew of no notes, no outlines that Brian's father had left behind. As we began work, Brian received a call from an estate attorney who had found keys to two safe deposit boxes that no one in the Herbert family knew existed. Inside those boxes were papers and old-style floppy computer disks that included comprehensive notes for “Dune 7.” Now we knew for certain where Frank Herbert had been headed, and we could weave the events of our prequels into a grand finale.
 
After this unexpected find, Brian dug through many boxes of papers that had remained untouched since his father's death. There, he also found more than a thousand pages of outlines, unpublished scenes, character descriptions. A gold mine of Dune background.
 
Now, after two successful prequel trilogies, we have finally written “Dune 7” — Hunters of Dune and next year's Sandworms of Dune. The fans will be able to read the long-awaited climax.