Return to the Rain Wilds was confirmed at Pat's Fantasy Hotlist interview.
According to UK SF Book News interview this will be a single book.
Quote from UK SF Book News interview: "This is NOT a direct continuation of Liveships or anything like that. Readers will get some glimpses of characters they've seen before, but not a full fledged continuation of any character's story. I want to be very honest about that. It does take place chronologically after the events in Fool's Fate. And of course, things that happened in that book are going to affect things that happen in the Rain Wilds and Trehaug. That is how the world works."
"I think I've decided that it will all be in third person, told by four view point characters." Robin's Newsgroup
Drafts 6 and 7 of the books prologue can be read from Robin's Myspace blog.
At the moment, the publishing information is a bit conflicted, amazon.co.uk lists both
- Hardcover Publisher: HarperVoyager (1 Jul 2009) Language English ISBN-10: 000729025X ISBN-13: 978-0007290253 and
- Hardcover Publisher: HarperVoyager (25 Jun 2009) Language English ISBN-10: 0007273746 ISBN-13: 978-0007273744
The first line is the original information, the second contains the same information as the HarperCollins site. We'll have to wait and see. The US release date is scheduled for January 2010. There will also be an audio book, Publisher: HarperCollins Publishers Ltd; Unabridged edition (1 Jul 2009) ISBN-10: 0007317093 ISBN-13: 978-0007317097