It seems I am behind the times with this book, and maybe even with the genre, because everyone in the Glasgow SF Writer's Circle seems to have heard of it already. In fact, it's not even my book; I gave it to son no. 2 at Christmas and then cunningly borrowed it from him.
I enjoyed it, with one proviso. I enjoyed the cluster of real and unreal well-known Victorian characters, all juxtoposed on the page together beneath the looming presences of Dracula and Jack the Ripper. Some of the action is truly horrible; some of the humour had ma laughing aloud. The characters and the dialogue are strong.
The one thing I didn't like was the inconclusive ending. Some books make a big thing of this sort of ending (The Crimson Petal and the White springs to mind) but in my opinion this shouldn't have been one of them. I wanted more of a resolution and perhaps more of a pointer towards future stories (which I gather from GSFWC do exist).
Overall, if you have a reasonably strong stomach, I recommend this book. I shall certainly keep my eyes open for more Kim Newman offerings.