The intrepid reporter Murray Waas has an exclusive: Bob Novak has cooperated with Valerie Plame investigators and they may not believe him:

Also of interest to investigators have been a series of telephone contacts between Novak and Rove, and other White House officials, in the days just after press reports first disclosed the existence of a federal criminal investigation as to who leaked Plame's identity. Investigators have been concerned that Novak and his sources might have conceived or co-ordinated a cover story to disguise the nature of their conversations. That concern was a reason-- although only one of many-- that led prosecutors to press for the testimony of Cooper and Miller, sources said.

Lending credence to those suspicions was that a U.S. government official questioned by investigators said Novak specifically asked him whether Plame had some covert status with the CIA. The official told investigators that Novak appeared uncertain whether she was undercover or not. That account, on one hand, might lend credence to the claims by Rove and other Bush administration officials that they did not know Plame was a covert CIA officer. Conversely, however, the fact that Novak asked the question in the first place appeared to indicate that he might have indeed been told Plame was a covert operative, and was seeking confirmation of that fact.