The Name of the Star by Maureen Johnson.
This is an nominee for Iowa Teen Award this year.
Book description from Amazon.com:
The day that Louisiana teenager Rory Deveaux arrives in London to start a new life at boarding school is also the day a series of brutal murders breaks out over the city, killings mimicking the horrific Jack the Ripper spree of more than a century ago. Soon "Rippermania" takes hold of modern-day London, and the police are left with few leads and no witnesses. Except one. Rory spotted the man police believe to be the prime suspect. But she is the only one who saw him--the only one who can see him. And now Rory has become his next target. In this edge-of-your-seat thriller, full of suspense, humor, and romance, Rory will learn the truth about the secret ghost police of London and discover her own shocking abilities.
My 25 cents:
I was not real excited about reading this book as I tend to like modern day, more realistic fiction. I was pleasantly surprised though that I was drawn in by the suspense and anxious to find out what was going on with the "new" Jack the Ripper killings. The setting for this story IS present day and the author did a great job of telling just enough about the original Jack the Ripper spree in the 1800s without making that the focus of this story. It looks like this is the beginning of a series of books, so our library will for sure be getting the next ones.