I couldn't see her as Lucy at all to be honest. My first reaction was kind of happy surprise to see Jolie is actually not giving up acting but that was quickly followed by a WTF! of her being Scarpetta. If not Jodie Foster I would have gone with Glenn Close or Meryll Streep or even Helen Mirren (all fantastic actresses but probably considered "too old" for the box office.)

Apparently Cornwall herself has approved Jolie so I'd say there's no turning back, though the movie is meant to be based on the books rather than taking one particular story so who knows what they'll change.