The GoF film being PG-13 isn't a rumor--WB's CONFIRMED it, to my delight. I'm glad they're not pulling any punches. These books just keep getting darker and more frightening, and I think it's good that WB isn't forcing the movies to be kiddified at all.
Matt, I would disagree with your assessment that Harry and Hermione would be a good romantic match. Harry and Hermione just don't have fun together; Harry and Ron can have fun, and we see hints that Ron and Hermione can have fun, but we especially see in Goblet of Fire when Ron and Harry are not speaking, Harry and Hermione just don't have a lot of fun together. I actually had this unshakeable kind of feeling from when I first read the books that Harry and Hermione were just so utterly platonic, and it wasn't until I read this essay (
https://www.sugarquill.net/index.php?action=goodshiprh&st=angua) that I could really pinpoint WHY they weren't romantically suited. It's got some excellent, realistic points about Harry's needs as a person and Hermione's role in his life. Of course, you may not have really commented on Harry/Hermione with the desire for a huge discussion on it, so I apologize if I'm getting too into things.
With the Lupin/Tonks thing, I was more thrilled for LUPIN to be in a relationship. He's a favorite character of mine, still vying for the favorite spot with Sirius, and his life has been so difficult and tragic that he DESERVES some love in his life. Tonks, from what we've seen of her, will be good for him, IMO.