I don't want to spend a whole lot of time on this one because a) there's more Harry Potter discussion coming as soon as I resume my crawl through past winners, and I'm going to post most of my thoughts on the series then, and b) it's only half a movie.
This is the first half of the adaptation of the final Harry Potter movie. It eschews the usual school-year format, as the series has come down to the magicians in a world at war with the protagonists on the run for most of the movie. To defeat the evil Lord Voldemort, they need to destroy a series of items called "horcruxes" in which the Dark Lord has preserved and protected pieces of his soul in a quest for immortality. Unfortunately, Potter and his pals don't know what most of these horcruxes are, where they are, or how to destroy them. This makes for an odd film, in which the protagonists are aimless and directionless for a solid chunk of the run time. When the Deathly Hallows novel came out, almost everyone complained about the lengthy wandering through the wilderness and arguing scenes. Well, after a few exciting scenes in the first half, that's basically what this movie is.
I think those potentially boring scenes play better on screen though. Screenwriter Steve Kloves (who adapted most of the Potter franchise) and director Yates use this as an opportunity to focus on the characters, especially Harry and Hermione (Daniel Radcliffe and Emma Watson, respectively, who give their best performances of any of the films). There's a telling scene in the film where the two dance to a song on the radio that some found cheesy, but I think is a nice reminder that we're dealing with teenagers who have the weight of a world on their shoulders. Scenes like these led to me liking this film quite a bit. In fact, I just watched the climactic, action-packed Part II over the weekend, and I preferred Part I. As a result, I can kind of see why this was nominated even though the solid sixth entry was skipped.
Still, it's just half a movie. It ends rather abruptly, and it's certainly not a complete story. As I understand it, the nominating rules have clear guidelines for serialized works (Blackout and All Clear is an almost identical situation). I think the nominators should have held out for the rest of this one. I'm not sure that the full two-part film is any greater than the sum of its parts (I don't think it is, honestly), but that does seem like a fairer assessment.