Well worth seeing! Saw it yesterday. They did make a couple of changes to move some Biblical events to other times and locations to help the story flow, but I was really touched by the characters as they were presented. It is sometimes hard for us today to remember just how remarkable (and unbelievable) the story was to those who heard it first. They put their lives on the line to defend a position they could not defend - what faith!
Read the book first, the book is always better than the movie.