The not yet titled book by Christie Golden will star Asajj Ventress and feature Quinlan Vos. It will be out next summer, and 2015 isn't all that far away. Not really.
According to Del Rey, the book is based on unaired Star Wars: The Clone Wars scripts. Dave Filoni was present at the Comic-Con panel when the annoucement came out, and StarWars.com reported him saying, "Ventress had become one of the most interesting characters…we had all this material, we had all these designs…This is based on scripts we had written with George Lucas…I’m super excited about this book."
I'm super excited, too.
h/t Star Wars Books and StarWars.com