In dealing with such charged, emotionally touchy subject matter, I was quite surprised that a German movie would portray Adolf Hitler as a human being. An evil, maniacal human being, but still a human being. Too many movies depict German soldiers as caricatures, inhuman monsters hell-bent on ideological extermination. But as the Milgram experiment found, perfectly normal human beings can be driven to perform atrocious acts by many factors, and I was pleasantly surprised at the depth of character development in Downfall.
The most chilling revelation in the film is that Hitler was human, not a raving lunatic, and thus his conscious decision to sacrifice scores of his own countrymen in the futile battle of Berlin is all the more terrible. And that's to say nothing of the concentration camps, death camps, human experiments, etc., etc.
Bruno Ganz did his part by turning in an astounding performance as Hitler, but despite the terrifyingly vivid battle scenes I found the picture in general a little too slick and over-stylized. A bit of grit wouldn't have gone astray, but you can't take anything away from the fact that it presents WWII in a completely different light to the Western point-of-view, which verges on propaganda.
(And of course, I couldn't get through Downfall's most famous scene without thinking of those scores of YouTube videos. For the record, this is my favourite.)