Dr. Joaquin Navarro-Valls, the Press Office Director of the Holy See, released a statement this morning of the Vatican's official position on the Holy Father's alleged comment on Gibson's Passion; among which is this: "It is the Holy Father's custom not to express public judgments on artistic works, judgments which are always open to diverse evaluations of an aesthetic nature."
I can see that, when a statement may create controversy, it may be better to say nothing at all, unless there is a crucial principle at stake. However, I would have hoped for a more transparent explanation from Dr. Navarro-Valls, rather than one that gives the impression of damage-control. I may be wrong, but I find it hard to believe that the Holy Father, upon receiving a work of art as a gift, or upon hearing a particularly moving symphony, has never expressed publicly his impression of the work.
One possible explanation is that the Press Office initially approved the release of the famous "It is as it was" comment; a statement of fact, intended to quell the simmering controversy over charges of anti-Semitism. However, upon learning that the comment was being used as an official endorsement in the promotion of the film, the Press Office felt pressure to back-peddle, from within the Vatican, in order to distance itself from implicit approval of Gibson, the man, being one in fractured communion with Rome. Again, it's only speculation. We may never know.
What I do know is that it is difficult to reconcile the statements made on all sides. With people's credibility on the line, I certainly hope that someone comes clean; otherwise several reputations will be tarnished.
Here is my post of the original announcement of the comment, followed by my post of its subsequent anonymous retraction, and Peggy Noonan's detailed recounting of the chain of events leading up to today.

I know some don't want to here anymore about this, but the whole debacle does give us a glimpse into Vatican politics. Sandro Magister published this column today, which recounts the basic story with a few other details I haven't heard before. He doesn't come to any definitive conclusion, but does sling some mud, just so you know.