Libby trial: Finally... Walter Pincus discloses who his source was who told him that Wilson's wife, Valerie Plame, has allegedly sent him on his mission to Niger, and also suggested that he was sent because of nepotism: Ari Fleischer.
That explains more why Fleischer only agreed to testify with a grant of prosecutorial immunity, both before the federal grand jury and trial. It is surprising that this information did not come up during Fleischer's own lengthy testimony.
It's interesting as to why neither the defense or prosecution brought this out when Fleischer testified. It would seem to help the prosecution's case, one would presume, because Fleischer learned the information from Libby, thus seeming to corroborate Fleischer's testimony that he learned about Plame from Libby.
Update: The Washington Post now has a long story posted online regarding Pincus' testimony.