I wanted to highlight this post by PZ Myers, mainly because it so neatly dovetails with what I was saying a month ago about The Reaping. I also did a TV episode about fictional atheist strawmen, which you can watch here.
In talking about the movie I Am Legend, PZ highlights a similar major problem with movie atheists, which is that the only time they are portrayed in a positive light is when they are a kind of "failed biblical Job", put through all kinds of awful tribulations until they finally crack and declare that there is no God. Even though this turns them into a sort of sympathetic figure, the fiction in the rest of the story always proves them wrong. As I said regarding a similar character in The Reaping, very few people really come to atheism that way.