Maybe cos I had high expectations for the movie since the past few episodes were really good...
Maybe cos I read the books & knew the whole story already...
But I felt this movie was too draggy, 90% dialogue, 10% action, no sign of Voldemort, no combat scenes, too much emphasis on the love stories amongst the main characters.
The highlight of the show was finding out who the Half-Blood Prince was, but towards the end, Professor Snape just walked up to Harry Potter & admitted that he was the Prince.

Oh ya, Professor Dumbledore died in the show, without any fight at all. Draco Malfoy was supposed to kill him but didn't have the guts to do so. And Snape just walked up from behind & killed him on the spot. Harry Potter's gang (Remus, Tonks, Arther Weasley etc) were supposed to be fighting with Voldemort's lackeys in Hogwarts, in their attempt to get to the Headmaster's side; but before they could reach him, he was killed.

Verdict: Read the book, you'll get a wholesome understanding of the story & a more exciting version. But watch the movie, if you have been watching every other episode. It's just something you have to do..