Miller is the leaker. She called Rove and asked his opinion about Plame recommending Wilson and then told him about Plame working for the CIA. Rove then passed this info on when asked by Cooper ie "Wilson's wife who "apparently works for the CIA".
That's my theory.
I agree.
And as far as leaking her name, it was on Wilson's own bio. Nobody had to leak her name. He did it for them in black and white.