Having seen Harry Potter and the Order of the Phoenix twice now, here's a review:
Both my wife and I disliked the film on the first showing, and liked it the second time we saw it. The book was the same for me, I've enjoyed it more after I read it the first time.
OOTP is a movie that is less than the sum of its parts. So much is right with that movie, and it yet it still seems to fall flat.
Bad:
The score. The soundtrack was terrible. For a long movie, it should have helped drive it. Instead it was completely absent in slow parts. When there was music, it often had no discernible beat. There were some good parts, and I noticed my daughter pick up her attention when the music did. But when there was music it seemed to fly around aimlessly and did nothing for the tempo of the movie. Had there been good driving music (like Bear McCreary does for BSG), this would have been one of the best movies in my opinion. With no music, it reminds me of a terrible movie watched during weekday afternoon on TV when I was home sick. You were too bored to turn it off, yet it made you feel worse.
Camera angles with Dudley: I didn't like shooting straight on with Dudley and Harry. Looked awful.
Mrs Figg. Harry gets attacked by dementors, and Mrs Figg acts like a bag lady collecting cans. A complete lack of drama kills this part.
Luna's makeup at the end scene when she found her shoes. Rather than look like she was bruised, it looked like she had a couple holes in her head.
I missed the Quibbler storyline where Harry gets his version published.
The lighting was too dark and the colors too muted. The movie should have been figuratively dark, not literally dark.
The editing was choppy.
I disliked Hermione looking out the window at the lightning after Sirius's head was in the fireplace. That scene was lame. Dialog was ok, but not the setup.
The shelves with spheres were too high to be believable. It was too CGI for me.
Good:
The acting was great.
The special effects, particularly the end fight were also wonderful.
Snape was awesome. I particularly like that the occlumency lessons appeared to hard, and that several were required. Movie 3 in the series failed to show how difficult the Patronous charm was to produce, and this movie succeeded with occlumency.
Luna Lovegood was perfect. Brilliant casting with her.
Harry's relationship with Sirius was built well.
The scene of Voldemort possessing Harry was well done. It would have been so easy to screw that up.
Condensing an 800 page book into a 138 minute movie was well-done script-wise. Hard to see that on the first showing because so much was lost that I liked. But I think the story was done well.
Umbridge's office was perfect with the cats.