First Scott Johnson took a whack at the story. Then, John Hinderaker, in great detail, shows that the person 60 Minutes relied upon for the most explosive charges is either lying or unstable.
What is surprising is not that Jill Simpson exists, but that CBS chose to put her forward on 60 Minutes as a credible witness, without disclosing the many facts that would have enabled the network's viewers to draw their own conclusions about Simpson's story. It seems fair to wonder whether, at some level, the people who run CBS and 60 Minutes are as deranged as Jill Simpson when it comes to Karl Rove and the Republican Party.
Gateway Pundit was the early leader in exposing this story and has a thorough rundown here.
UPDATE: John Hinderaker discusses his findings in a radio interview.