The next title is Skin Game. At the time of this posting, there's no content there other than the title announcement. When Ghost Story ended, we knew what was happening next and it was easy to interpret the next-announced title Cold Days. (The first time I read the title announcement on that one, I was sure it was Cold Day, which I liked even better. I wonder whether I was mistaken, or why it changed. Alas.) But the end of Cold Days left enough to happen next that it wasn't evident where it'd pick up, making the interpretation of the title more of an adventure.
But I'm keeping my theories to myself. I wouldn't want to spoil anything for an unsuspecting reader. But you can always email to share theories about Dresden :-)
I especially won't spoil things in previous books, like what Butcher must be teasing regarding the name of the oldest queens of Summer and Winter. Muhuhahaha! And so we wait for the publication of the next Dresden book – let the suffering begin!