If I think I'll like a movie, I go to see it even if the critics didn't like it. They have biases too. If you don't like a certain type of movie (for me it would be horror flicks or most sci-fi), even if it's really good, you're probably not going to give it a rave review. I've loved some movies that the critics hated and hated some that the critics loved.
I haven't seen the "Passion of Christ" either. Mel's movies tend to be too violent for me. Also, the movie came out during the first week of Eastern Orthodox Lent, and we aren't supposed to go to see movies during Lent, and particularly not during the first week when we're supposed to be in church just about each night for services. From what I've heard, I really don't think I want to see the movie, even on video. I don't like extremely violent movies and images tend to stick in my mind and I have trouble getting them out, so I'm better off not watching them.