Well, an article in the Catholic Herald gives some hope that the movie will actually be interesting and fair (Highlights mine) :
The making of this film has been something of a voyage of discovery for me. I can’t be the only Catholic in the world who had major apprehensions on April 19 2005 as the conclave made its decisive choice to elect the first German pope since the 11th century (I don’t count Adrian VI, born in Utrecht in 1459, part of the Holy Roman Empire). I was worried about whether the former head of the Congregation for the Doctrine of the Faith might be just a little too polarising. I am no expert of conclave arithmetic, but my hunch was that he simply had too many doubters inside the College of Cardinals to get the required votes. Wrong. And I have been wrong about him, too. It is not that he has changed radically since taking up the papacy; it is simply that when you have to make a one-hour programme on one of the most clever and gifted people on the planet you have to look behind the headlines and the angry rants on the blogosphere. In short, you have to do justice to the man as best as you can.
The whole article is worth a read. Basically, as the filmmaker read Benedict's works, interviewed people who know him, and got to know the "real" Benedict, he learned something important about Orthodoxy--something I can't stress enough. Orthodoxy is NOT something that fits into a neat little political box manufactured by the world.. It's not about liberals and conservatives. It's BIGGER than politics. Benedict is not "conservative on liturgy and abortion but liberal on economics and the environment." He simply views EVERYTHING through the lense of God's relationship to man and man's realtionship to God.
Anyway, after reading the linked piece, I have hope that the BBC might manage to produce a decent documentary on the pope.