"Lying for Jesus"
PZ Myers , a biologist who is featured in the movie, and thanked in the credits, tried to get in to see the movie he had been told (prior to being interviewed) was going to be a movie called "Crossroads," examining the relationship between science and religion -- they didn't tell him it was a creationist hit piece on "evolutionists" like him. (They're now claiming "Crossroads" was merely the working title of the film, but it turns out they registered the Internet domain name for "Expelled" before they interviewed Myers and never did register a domain name for a movie called "Crossroads.")
But while he was in line, someone at the screening recognized either his name or his face, and a security guard approached him and told him he wasn't welcome at the movie he'd registered to see, and he'd be arrested unless he left. In short, he was expelled from "Expelled."
So he left, but the people running the screening were nice enough to let in his family, and his invited guest -- who turned out to be Richard Dawkins.
Here's Myers' take on the expulsion (more here), and Dawkins' take on the movie itself, and a New York Times article desperately trying to be even-handed about it without coming out and calling the creationists liars as they desperately try to spin the situation.
And here's a video of Myers and Dawkins discussing the event afterward .
And here are a bunch more links on the affair.