I first heard the idea that Jews were responsible for the death of Jesus at about the age of 21. I was raised in a true Christian home, and honestly never heard this hogwash before.
In my family we are loyal only to the religion of the Bible. If you can't prove it by the Bible, it's not our belief. Like early Protestant Reformers, we reject the Catholic Church, but we also reject most of Protestantism as well. Thus our religion can't be defined by examining what a majority of Christians say or said at one time.
The idea of holding Jews responsible for the death of Jesus is totally foreign to the New Testament. The standard answer you'll hear to this nowadays is that we are all responsible for the death of Jesus: He died for our sins, and would have died for even a single one of us. That's theologically true, but I wanted to point out something that might mean more to those of a more secular mindset.
The fact is that all those responsible for the death of Jesus are dead. Noone living today is responsible for the death of Jesus in a strict sense. When the Bible talks of Jews and Romans crucifying Jesus, it nowhere suggests that ALL Jews are responsible for the death of Jesus, but only the specific Jews of that generation who chose to be involved (mostly religious leaders, and not even including all of them). Genetic hereditary guilt is foreign to both the Old and New Testaments and is an idea condemned in Ezekiel 18. (Yes, the Catholic Church and the Reformer Calvin were totally, blasphemously wrong about this.) No Jew living today (or in the Middle Ages) is responsible for the death of Jesus.
There is a statement at the crucifixion of Jesus from the Jews involved when Pilate attempts to disclaim responsibility that might cause confusion. They said, "His blood be upon us and on our children." Let me assure you that no matter what they said, they did not cause God to change His mind about Ezekiel 18 and hold their children responsible for their actions. (Let me also assure you that even though Pilate washed his hands to proclaim his innocence, he was still thoroughly responsible for what he did, too.)
The Bible itself does not hold anyone living responsible for the death of Jesus, though it does teach the theology that He died because of our sins and we are in that sense responsible. The idea of killing Jews or anyone else because of the death of Jesus is not only absurd in the light of the religion of the New Testament, it's a blasphemous excuse for murder put forward by wicked men who dared to justify the blackness in their hearts by applying the name of God to their cause. As the Bible condemns those who would use the Lord's name in vain, I imagine these people receive some of the most severe condemnation imaginable.
Addendum: What I'm trying to say is that if Mel Gibson's new movie adheres strictly to the Bible, it will not be anti-semitic, even if it uses lines that have traditionally been interpreted by evil, twisted people as anti-semitic. I've heard tell that his movie is based not only on the Gospels but on the "visions" of some man from the 18th or 19th century, though, and I haven't seen the movie, so I'll reserve judgment.