I thoroughly enjoyed it, and I'm so glad! It stayed mostly true to the book. But one thing it left out should definitely have been included--Harry should have explained to Ron how much Hermione had missed him and how he (Harry) loves her like a sister. Omitting that could cause ambiguity in those who may not have read the book. And they should have talked about the diadem at the Lovegoods' house to set up the background for what happens later.
Overall--I didn't realize the 2 1/2 hours were over until the credits started to roll! I was surprised it was already the end of this first part, but that's where I thought it should break so, well done!!!!