Saw it 1201 AM with my 15 yo daughter and her friend (I'm the 58 yo dad). Before the movie I was: why did I agree to lose sleep to see this ?(though I liked the book very much and am reading New Moon now) Afterwards, it was: "Wow. That was great. Definitely worth losing sleep over. The 2 lead actors are amazing, especially Bella. Seeing it with a large enthusiastic audience of maybe 95% teenage girls helped. It was very intense, and I was blinking back tears on several occasion. It brings back the feelings of first teenage love.
Movie wasn't entirely faithful to the book, maybe 70%, but it was very high quality, similar to, perhaps better than, the Harry Potter series.