I suspect his conversation was on the phone. Recording phone conversations in DC is not legal unless both parties agree to it.
We know that Rove's attorney said Rove told the Grand Jury that "I heard the same thing!" when asked to confirm Plame being Wilson's wife and that she had gotten her husband the job.
I suspect that Novak only told the Grand Jury that Rove did not confirm that Plame was Wilson's wife who got Wilson his job. "I have heard the same thing!" is not a confirmation. So Novak then contacted Harlow who did confirm that Plame was Wilson's wife and that she got her husband the job.
Note that Novak also says his recollection of his conversation with Harlow differs from Harlow's recollection.
If Rove "Remembered" things from their converstation that Novak "Forgot", then that explains the differences.
You can not indict Rove for "Remembering" something that Novak "Forgot."
It is also likely that Harlow "Remembered" things from his conversation that Novak "Forgot."
I think Novak is just saying to both Harlow and Rove... I tried not to "Remember" anything that might have given Fitzmas a reason indict you. If Novak "didn't remember" there can be on purjury indictment for Harlow or Rove.
I agree with you 100%, but I don't think this necessarily applies to Novak. The item below clearly indicates that he knew exactly what the legal ramifications would be if he refused to cooperate with the prosecutor (highlight is mine):
My attorneys advised me that I had no certain constitutional basis to refuse cooperation if subpoenaed by a grand jury. To do so would make me subject to imprisonment and inevitably result in court decisions that would diminish press freedom, all at heavy personal legal costs.
He did. And I believe he said everyone would be surprised.
I wonder what the substance of the "differed from my recollection" was all about. And doesn't Novak record his conversations?
I read (and who knows how reliable the source?) that Rove recalls that when Novak asked about Valerie Plame, he said "I heard that too." And Novak recalls that Rove said something like, "Oh, you know that too?"