As the series progresses, Rowlings extensively adds more layers to the story giving the readers a depth view of what's to come. As such, it is becoming increasing more difficult for the movie makers to capture the essence of the books. This adaptation didn't capture the intensity the book had. This was the story that changed it all, the discovery of how to kill Voldemort and the build up was lacking.
The biggest event was that of Dumbledore's death and yet when he died, the emotion of losing such a lovable character was lost. Yes, things change from book to movie, but the previous adaptations held true to the emotion of the scenes. You could feel the sadness when Diggory died, the pain when Harry saw his godfather killed. Dumbledore deserved just the same.
Voldemort was also no where to be seen. In the book, he invades Harry's mind, in the movie is his merely mentioned. As a book lover, you may not like this adaptation. As a movie goer, it's worth seeing.