My 12 year old daughter and her friends had read the book and begged their mothers to take them to see Twilight. I hadn't read the book, and the other moms hadn't either. Overall, I thought the acting was only average, the makeup is more than a little hokey, but the storyline is good. It kept my interest and all the girls in the theatre were "ooing and awing" over everything Edward did. My daughter really liked the movie and it wasn't too scarey. Although, if your preteen is sensitive to scarey stuff, I'll warn you that my daughter has slept with the light on and music on low since she saw it.
This movie left my husband and I a little sad and it has stuck with me. Our kids loved it, it has many adorable scenes. The overal message is directed toward adults and is disturbing. The fat people who never interact, exercise, eat real food, cuddle their children, or do anything remotely characterized as work are too close for comfort. Kids will love the movie, but adults should be prepared to feel like they've had their hands slapped and told "shame on you!".