Starting in August of 2003, the new episodes of the show had been premiering every sunday at 11:00. (The first time an action show had kicked off a block of Adult Swim, I believe) Well, after 3 episodes of direct cliffhangers, act 26 was scheduled to air on October 26th, the night of their special Halloween themed night / webcam party where they claimed that "We will kill you" or somthing to that extent. But unfortunately that night they aired act 20, immediately the message boards were flooded with threads asking what happened to the episode, what the hell is going on, etc. Some speculated it was a "Cartman's Mom" like prank they pulled for the Halloween special and to make matters worse some at the webcam party began to insult the people on the message boards.
"At the webcam party on Halloween, staff members (there was nobody there from Action except Dennis, who was acting as the door guard) were making fun of Big O when it was on until one asked "Is anyone WATCHING this shit?" before turning it off. They flipped back when Brak premiered." -livingfruitvirus
They later apoligized and explained that the whole thing was a big mix up, and to rectify the whole situation they had to push back a much hyped never before aired episode of family guy to premiere act 26 of The Big O. Then when they finally showed it, they aired 30 second of act 20 and then cut to a card which said somthing like "We had to do it"
Moral of The Story: Big O had (and still has) a much larger following that most people give it credit for.