There is a new review of Bookhounds of London by Andrew Behaut here.
Not only does Bookhounds make me want to run a game, it makes me feel confident that I could run that game well. Many supplements place the burden of extracting a game from their contents on the Keeper; this book does not. As an unconfident and less experienced Keeper, this is excellent. If you only get one supplement for Trail of Cthulhu, this should be it.