Woohoo, got mine!
It's set the February after White Night, and it does contain spoilers for Thomas' big secret revealed in that book. It also has big, honking spoilers for Blood Rites and Proven Guilty, for those concerned about earlier novels.
Where did you get it? I have no idea what my work schedule for next week is, but I am definately going to use one of my days off (if any) to get the book, even if that means taking a bus or two to get to one of the bigger bookstores.