Even if you haven't seen it, you probably know the list of scenes that reviewers are pointing to as the most effective: Mrs. Lipscomb reading the last letter of her son, Sgt. Michael Pederson, the several minutes W. spent at his photo-op after learning of the attacks, the comparison of his service record obtained prior to its release and the censored version released by the White House, the scenes of American soldiers wondering what they're doing in Iraq, etc. The scene that got the biggest chuckle out of me was the one were Mrs. Lipscomb, walking up to the White House talks with a protester about losing her son, is rudely accosted by a (very typical) smug women who tells her the protester is "staged" and starts sniping at Mrs. Lipscomb, demanding to know where her son died, as if she were a prop as well. Finally realizing she's horribly wrong, the women stomps off, dismissively telling the mother of the dead serviceman: "Well, lots of other people died, too." Republican manners exemplified: shrill denunciation ending with one last spit in the face before ducking away the from the issue to resume wallowing in self-righteousness.
[Update: Movies.com box office results for this weekend shows Fahrenheit 9/11 number one with $21.8M from just 868 theaters compared to the second place movie's $19.6M from 2726 theaters.]