I was slightly annoyed at the balance of the film, too much silly teenage romance, not enough climactic final showdown.
That said, the silly teenage romance was surprisingly good. The scene with Harry and Ron lying in bed (how does that NOT sound bad?) talking about girls was a masterpiece of deadpan and awkwardness. Likewise, Hermione's breakdown over Ron and that girl (who is named ONCE in this film by my count, about 30 seconds before she ceases to have a speaking role) was actually pretty tragic, once you get past the fact that all the characters are emotionally stunted and pine longingly after each other for MONTHS, YEARS even. Christ, I think I know maybe 3 people with that sort of passive-whiny attraction, forget an entire school of them.
The sectum sempra scene was fantastic. The fight before was very nicely done. I like how the kids are starting to do silent-casting, but only for really crappy spells. And the shots of Malfoy bleeding out as Snape heals him were pretty bloody for a 12.
Bringing me nicely on to: Malfoy. Every single shot of him is gold. Why could he not have been this good in the last films? He's brooding, he's clearly cracking under the strain, but his nastiness (FACE-STOMP!) still comes through.
Then when the action does come: It's anticlimatic. The two added scenes (Death eaters trashing London, Bellatrix burning down the Weasly house) are great. Helena Bonham Carter is perfect as Bellatrix. She captures the sheer maniacle GLEE at destruction.
The fight against the water-zombies was really well done, and gave Dumbly a nice bit of send-off ass kicking. His death could have been done better, the actual A-K happens off shot, it cuts from Snape, to Harry's shock, to falling corpse off a tower, with stupid epic music playing. All I could think during that scene was "Damn, this is not quite as good as Gandalf's death"
The funeral is gone (Current guess is that it replaces the wedding as the opening of the next film) but is replaced by a fantasticaly touching scene when all the school dissolves the Dark Mark in the sky. Ron's sole moment of coolness in this film (in this series?) is being the first to twig and join in when McGonogall lifts her wand. It's quite telling that in the final talky scene between Harry and Hermy, Ron is sat in the corner and never speaks. Grint's a better actor than this, if they give him some decent lines he can do well.
All in all: A Mixed bag. But if this is the guy they have directing the Book 7 films I think we're in for a treat. Film 7 he'll be able to do the emotional stuff well, and provided he gives the action in Film 8 the screen time it deserves (and I fail to see how he can NOT do that) it's going to look amazing.