I agree with you dialupinternetuser. I was listening to Mugglecast (a Harry Potter podcast), and they were talking about how they left out WAY too much Kreacher stuff because he becomes quite important in HP6 and 7! And there hasn't really been any quidditch in the movies for a while, which is rather disappointing (maybe the special effects are too expensive?). However, the locket & Regulus Black comes into the story in Half Blood Prince, although Sirius does mention his brother Regulus in book 5.
The main thing that I've been disappointed with the movies is how they NEVER introduced Bill or Charlie Weasley! What are they going to do in movie 6 when Bill and Fleur are engaged? Argh.