I think there is enormous cause for hope here. And if the film has positive effects in the Muslim world, a great deal of the credit will have to go to the Jewish groups that protested its release. This would be a double irony: the film gains popularity because they opposed it, and they benefit from the increased popularity. I hope that in twenty years we will be having great arguments about what was the more powerful influence leading to the great modernization and pacification of the Middle East: the liberation of Iraq or the release of The Passion of the Christ.
Most Mideast Muslims have never heard the gospel story, only a highlights version heavily filtered through Islam. What an incredible opportunity this is! Their own hatred is leading them to seek out a telling of the gospel story.
While The Passion hasn't shown any tendency to stir up anti-Semitism among the generally philo-Semitic American Evangelicals, will it fire up already anti-Semitic people? Possibly. Generally you expect people to get out of a movie what they bring in with them, but I wouldn't be so quick to discount the power of God. I have been praying, without a whole lot hope, that the Middle East would be opened to the Gospel. (I haven't been praying for mass conversions so much as that the people will be given the chance to hear the Gospel and freely choose whether to believe without fear of reprisal.) Now I'm starting to hope. I would encourage all Christians to pray that the Holy Spirit will work in the Middle East, and that The Passion might be an instrument of this work. That, as in Genesis 50:20, what men mean for evil, God means for good.