My enjoyment of this generally awesome story was harmed by a lack of sympathy for Pearl. I mean, she was stylish and interesting, and her characterization was extremely strong. She was also a murderous, larcenous, cold-hearted bitch. I understand that being a woman in 1800s America was rough, but she liked to rob people for fun, blatantly used and manipulated everyone around her, and at least once tried to kill a woman out of a momentary fit of pique.
While I normally have a place in my heart for anti-heroes - admittedly, a small place, as anti-heroes are not my favorite idiom - I found the ending a little too disturbing. I mean, Pearl is going to raise a kid. Pearl - borderline, antisocial, possibly even sociopathic Pearl - is going to raise a kid. I shudder to think what kind of childhood that poor kid is going to have.
So, in the final arithmetic, a clever and well-written story, with a strong voice and a fascinating permise, but I just didn't like the character enough. I think I would have preferred her to either experience a little more growth or rot in prison for the rest of her life :-/.