So I finished Halfway to the grave yesterday and have been mulling over it ever since. I had a time, while reading it, trying to decide whether it was PNR or UF, and based on the ending, I'm going with Urban Fantasy. It definitely sets up for the series, and I'm looking forward to the next book.
Not really spoilers, but...
One thing I had trouble with was the relationship between Cat and her mom. Cat is a half-vampire, the product of a rape of her human mother by a new vampire. Her mother hates all vampires as a result, and is happy that Cat is going out and killing vampires, starting when she's 16 years old. It almost seems like she doesn't care whether or not Cat would get hurt or even killed, as long as Cat is killing the "evil vampires." As Cat, that must be crushing, being half-vampire herself. Cat's mother holds such hatred towards all vampires, she seems to hate her daughter at times. I hope that her mother can grow some in the following books.