Wizards of the Coast have a Cityscape Excerpt up:
- Cityscape Table of Contents
- Blackwall Blackwall (Chapter 1: The Scope of the City)
- City Districts: Magic, Necropolis, Warehouse (Chapter 1: The Scope of the City)
- New Spells (Chapter 2: The Urban Adventurer)
- Villains: The Symbol (Chapter 4: Events and Encounters)
- New Monsters: Siege Golem (Chapter 4: Events and Encounters)
I didn't see any other mentions of Kaddas, in the excerpts other than the Blackwall excerpt, but Kaddastrei is mentioned in the Table of Contents (so maybe there is more about Kaddas there).
Ripvanwormer said that Blackwall was "once part of (Kaddas)", but the Blackwall excerpt says: "Citizens do take their duties seriously and train hard, ready to defend Blackwall and Kaddas against any invader." I don't see why the people of Blackwall would be ready to defend Kaddas, if they are not citizens of Kaddas. Maybe something else in the book clarifies what Rip said.
The New Spells section mentions "Boccob or Wee Jas" suggesting to me that this book would be set on Oerth. And the New Monsters section has suggestions for using the Siege Golem in Eberron and Faerûn (which makes me think that this book is set in neither of those places by default).
Has anyone seen any mentions of Kaddas elsewhere?
Did any of the Living Greyhawk regions claim it? (Did any of the Living Greyhawk regions claim any of the other places in Cityscape?)
Could Kaddas be part of the New Koratia region or some other place between the Flanaess and the Sundered Empire?
EDIT: Zeromaru X says that Kaddas is in Nerath.