I can't say that the first half of "The Deathly Hallows" is a perfect movie, and it's certainly not the best of the series. (That would go to whichever of Azkaban, Goblet, or Order I've seen most recently.) But it's miles better than "Half-Blood Prince".
The most unfortunate thing about this film is the palpable feeling of disorientation since there's not a single scene in Hogwarts. Harry (and, by proxy, Hermione and Ron) are outlaws, missing their final year at the wizarding school because they're on a seemingly impossible mission to find and destroy the artifacts that contain the shards of Voldemort's soul. And in this two-and-a-half hour installment, they only manage to find one, while they also manage to lose a number of friends in the process.
The least unfortunate thing about "Deathly Hallows Part 1" is that it's almost all about our three heroes. Ron and Hermione got short shrift in the last film, I thought, and having all three of them stuck out in the wilderness, getting on each other's nerves (and generating some big laughs in the process) is enjoyable, at least for someone who really likes these characters.
But, make no mistake, this is definitely a "Part 1". The ending is a real low point for Harry, and a real high for You Know Who, but that only cements my desire to see "Part 2" next year.