Michael Moore shouldn't be trusted. While I do agree with a marginal amount of his opinions in a general sense (Bush shouldn't be President, and the current war is illegal an unneccessary), Moore himself is known as a trickster and attention hound. He grew up in Flint, Michigan, and I've had the opportunity to meet some of those who used to talk to him when he lived there. They all agree that it's not beyound Moore to pound out controversial bullshit just for the attention, weather it's his actual opinion or not.
Don't trust me? Ask BenJeremy. He grew up with him, and has posted about the same opinion of Mr. Moore.