Readers might have gotten the impression from this Times article that James Comey never signed off on the NSA program. Not true, according to Pete Williams of NBC

MATTHEWS: Let me ask you about the opposition within the government.
What`s stunning to me, I guess, is when you read about how these people –
even Ashcroft, a hard-line conservative not known for his civil liberty sort of
sensitivities, saying he didn`t want to go along with this.
You`ve got Comey, the number two guy, the guy who was acting as A.G. saying
he didn`t want to sign on to it. And you hear about these other reports coming
out of “Time” magazine.
It wasn`t like the president was even getting support from his own people for
this effort.
WILLIAMS: Well, I think that`s something we’re going to learn more about,
Chris.
There does appear to be something here where both Deputy Attorney General
Comey and Attorney General Ashcroft were concerned about technical aspects of it
and concerned about how it was being carried out, the sort of pretext that the
NSA needed to start monitoring someone.
But once those things were worked out, my understanding is from talking to
current and former Justice Department officials that they then agreed to the
program.
And one former associate of the deputy attorney general`s said today that at
one point Comey was among those officials urging the “New York Times” not to run
this story, that he ultimately accepted the legal basis for the program after
his initial objections were resolved.

UPDATE: Michelle noted this exchange yesterday, and has the video.