Newsweek fingers the odd man out:

So who is Novak's source—and Woodward's source—and why will his identity take the wind out of the brewing storm? One by one last week, a parade of current and former senior officials, including the CIA's George Tenet and national-security adviser Stephen Hadley, denied being the source. A conspicuous exception was former deputy secretary of State Richard Armitage, whose office would only say, "We're not commenting." He was one of a handful of top officials who had access to the information. He is an old source and friend of Woodward's, and he fits Novak's description of his source as "not a partisan gunslinger." Woodward has indicated that he knows the identity of Novak's source, which further suggests his source and Novak's were one and the same.

Has anyone asked Mark Felt?

In related news, the Washington Post spanks golden (olden) boy Bob Woodward for failing to be, ahem, entirely upfront about his Plameish insider information:

It boils down to this: There ought to be clear rules, easy for readers and Post staffers to understand, about Woodward's job at The Post. He has to operate under the rules that govern the rest of the staff - even if he's rich and famous.