I saw HP4 yesterday. Before I list the flaws, I'd like to describe my experience a little. My sister told me not to say anything if I didn't like it, which of course I promtly forgot about and began mumbling under my breath when they did something wrong, so I was basically mumbling throughout the movie. My sister kept telling people I hated the movie, I didn't hate it! I simply feel violent dislike for Kloves at this moment.
Now for the flaws! For your convenience, they are listed in chronological order^^
1. The very beggining, Barty Crouch(jr) is in the Riddle House with voldermort and wormtail.
2. Harry is woken from his dream by Hermione, because he is already in the burrow.
3. Mrs. Weasley, Winky, Mr. Roberts and Ludo Bagman are not in this movie.
4. Harry and Ron have no idea where they're walking to when they leave for the cup.
5. Cedric comes into the movie by jumping out of the branches of a tree.
6. There is absolutely NO concealment of wizardry at the QWC.
7. There are no team mascots.
8. The actual quidditch game is not shown
9. The Death Eaters appear roughly two seconds after Harry Hermione and the Weasley's return to the tent.
10. Harry is knocked unconcious in the campsite, the woods is non-existent.
11. The entire campsite is burned to the ground.
12. Barty Crouch Jr comes looking for Harry in the wreckage.
13. Immediately after the QWC, the scene changes to the Hogwarts Express.
14. Weasley's Wizard Wheezes, is NEVER MENTIONED.
15. Boubaton (spelling?) and Durmstrang arrive at the beggining of the year.
16. Boubaton is all girls, Durmstrang is all boys.
17. The Goblet of Fire is immediately brought out.
18. Harry and Ron's fight is just plain stupid.
19. Hagrid tells Harry that Ron knew about the dragons because Charlie brought them from Romania.
20. The Potter Stinks badges don't come until the day after Harry sees the dragons.
21. Malfoy is turned into a ferret outdoors, is not bounced, and is only in the movie a total of three times.
22. The curses scene in moody's classroom is out of order and wrong.
23. Neville does tell Harry about the Gillyweed, and steals it for him.
24. I've skipped a few inaccuracies here...
25. The Merpeople cannot speak above or under the water, and they are all female.
26. The Grindylows have tentacles
27. There is not statue and Harry just uses his wand to sever the rope from the very unrealistic looking "body" of Ron.
28. Hermione kisses Harry on the head when he comes out of the water, making more people who have not read the books think that their friendship is more than platonic.
29. Hermione wears a pink dress to the ball, a mortal sin.
30. Hagrid and Madame Maxine never have their argument, because the grotto full of fairylights is non-existent.
This is the absolute last one I'm doing because this will take much too long if I do them all.
31. In the maze (I'm skipping enough flaws to fill a warehouse) there are NO creatures, and NO spells, and NO blast-ended skrewts whatsoever. Its just a goddamn maze, in which you can "lose yourself" as the new Dumbledore says.
I'm really missing Richard Harris right about now.