In a recent interview, Jim mentions the name of the second book. I'll have to review the video as I was watching it for Dresden Files.
But he does say that it will center around the Olympian Spire and that Spire Albion and Spire Aurora will be jockeying for alliances trying to convert spires onto their side. He kinda talks about it like he does Peace Talks in that everyone will get together, be nice, etc suggesting that there will be some intense fighting between the two spires at Spire Olympia.
This is the thread I made after watching the video posted on You Tube. It is here where I gathered that information, not sure exactly which part it was from. I'll let someone else view it for the title of the next book, as I already watched them.
http://www.jimbutcheronline.com/bb/index.php/topic,46174.0.html
