Here is a link to the original Robert Novak piece that started this story (click here).
And this is the paragraph at the heart of the scandal, "Wilson never worked for the CIA, but his wife, Valerie Plame, is an Agency operative on weapons of mass destruction. Two senior administration officials told me Wilson's wife suggested sending him to Niger to investigate the Italian report. The CIA says its counter-proliferation officials selected Wilson and asked his wife to contact him. "I will not answer any question about my wife," Wilson told me."
Seems to me that Novak's current argument that Plame was not a covert operative, but an analyst and that this was common knowledge, is not supported by his own column, and if that was the case, why would the CIA ask for an investigation in the first place?
Edit: Josh Marshall makes a similar point here and here.