It took three tries by David Yates and his team, but he finally got some real mileage out of the book material in Harry Potter 7 Part 1. The film was very different in scope and focus, and because of it, it shows its strengths very clearly, as well as some flaws, because its not perfect.
The flaws are that its an adaptation, not a book, so its clear that you have to be familiar with the story from reading it to really understand this film and what's going on to any depth. That's been the weakness of all the Yates films. Luckily, he had 2.5 hours to use, and took his time with this one. At least we get a good explanation of the Deathly Hallows, if there are other parts that are made less clear. The other weaknesses are that they can't dwell on the secondary characters now, as you could in the book, because there's no time to waste.
However, the trio of Watson, Grint and Radcliffe do something really well this time out: They carry the film forward pretty much by themselves. They couldn't do this years ago, because they weren't old enough to act through some emotions. However, now, the three actors clearly have a nice bond that works to their advantage on screen, and they use all of the past history to make us care about what's going on. They are able to be front and center, and fill the screen. There's a lot to show, too. Chases, emotional/relationship tension, and this time, the fluid script keeps things moving, even when the characters aren't. The descriptive word for this film is tension, and it's well done with that in mind.
Camera work and editing is smoother, although sometimes the jumps are a little abrupt, and some scenes are perhaps a bit shorter than they could have been. Nevertheless, the sense of purpose, and the quest that's before the characters is fully revealed here. We get a nice set up for the big finale, especially where the big weakness is in Voldemort's plans. All three of the heroes turn in nice performances, and they are much more natural than they ever have been. As usual, the supporting characters get little time, but it's used well, and the narrative manages to keep the tension I mentioned, even if you know the books well.
As I watched this film, I was thinking it's also the end of an era, and people that don't like these films are missing something. But then I thought... maybe they can't help it. All I can say is that you have to remember that this isn't supposed to be Citizen Kane.
They are books that have been enjoyed by millions of people young and old, and everybody views this and the characters through their own unique lens. Some people can't wrap their head around fantasy environments, and that's why they don't enjoy it. That's just the way some people are made. For the rest of us, if you put aside all biases, it's just a great set of adventure stories in a very creative and deep mythology. It will be hard to say goodbye to these films that have defined a decade of entertainment. I've read the supposed successors to these books,(look on any bookshelf at a store) and they're poor imitations by comparison. This is an original story, and although it borrows from some of the great authors, it stands alone. Millions of readers enjoy it, and that ought to tell you something about why people want to see these films done well. They've invested so much.
So, to sum it up, this time around, it's excellently done, with high production values for sound, lighting, effects, and a script that's better than most of the prior 6. It did its job to set up the second half of the end story. I'll be there to see it.
Note: There are some very chilling sequences. The young kids (6-7?) seated to my left couldn't take some of it, so if you're taking young ones, talk to them first. Even fantasy violence can be scary to a mind untrained in any kind of death.