First, the movie did rather seriously soften the anti-Catholicism of the book on which it was based. I particularly noticed one place where the book had essentially said "Christianity just borrowed everything from other religions", the movie went with "new religions often borrow traditions from older religions to ease the transition." Thus the choice of Dec. 25 for Christmas went from a Christianized version of the pagan celebration of the winter solstice (the book) to a convient time to celebrate the birth of the son of God (the movie). I guess this sort of thing is what the film producers meant when they tried to suggest that the movie was actually pro-Christianity.
Saying the movie is pro-Christian is going a bit far, however. Angels & Demons retains a significant number of damaging inaccuracies like the fact that science and faith are consistently painted as opposing forces throughout history when in fact an astounding number of science's greatest minds have been devout Christians. Furthermore, Galileo is painted as a scientific martyr persecuted by the Church when this simply does not fit the facts. Galileo was at odds with the Church, of course, but it seems to me that the conflict emerged from his disagreement with scientific status quo about geocentrism. This theory was backed by the scientific establishment of the day which was, in turn, backed by the Catholic Church. Thus the Catholic Church was the enforcer of the determination that Galileo not teach heliocentrism until further scientific inquiry could be conducted. To say that the Church persecuted Galileo for his blasphemous heliocentric theory is simply incorrect.
Angels & Demons also contains a signficant number of snide comments like "Be careful...these are men of God, after all". Such comments are fewer in the movie than in the book, but they aren't exactly few and far between here, either.
On the whole, the movie has been much-sanitized. Whereas the book was extremely anti-Catholic, and by extension, to some degree anti-Christian, the movie "plays nice." Apart from the misrepresentation of the science/faith controversy, Ron Howard seems to have learned his lesson from The Da Vinci Code: check your facts. Most of the blatant historical inaccuracies in the book Angels & Demons have been removed from the film version.
