It is really bizarre... First movie he never wears anything but robes, it seems, but now characters like hermione are taking any opportunity to try and look hot in normal clothes and half of hogwarts is running around like little muggles.
Malfoy, surely you've come to expect that after all these movies? A 767 page book to a two hour movie...something's gotta give. At first it infuriated me, but now I've decided to look at it positively as what they managed to do well. For example they wanted to split up Harry and Cho, but not have them hate each other. In the book that took a date going wrong very wrong, then the publishing of rita's article and harry losing his broomstick. In filming terms, that would involve taking over a village the size of hogsmeade and filming 10-15 more minutes of content for millions of dollars. But instead they had cho as the betrayer, but later revealed it was only due to veritasaerum. Ultimately, its not optimal (Who wouldn't want a ten hour movie?) but they had to do something, and they could've done it alot worse. In fact this movie had more quotes from the books than any other - entire convos were directly out of the book, for example parts of the trial. The main glaring differences really were in characterisation; particularly dumbledore.