I really enjoyed this movie. It actually made me appreciate the novel more and realize that I liked it more than I originally thought I did. I rated the novel a 3.5 and I'm starting to think it's more of a 4 or even 4.5. With the opening scene all of the events of the novel rushed back to me with warm feelings like spending time with a good friend.
Alex Pettyfer did a wonderful job as Number 4/John Smith. He was a little more cocky than I expected, but overall was pretty convincing. I was pleasantly surprised to see Dianna Agron (Quinn from Glee) play Sarah. I think she was perfect for the role. I loved her edgier attitude and artistic side.
The movie stayed somewhat true to the book. There were many things left out that the audience may not have needed but I thought would have been really interesting and visually exciting to include (such as John training). I also think a little more background about why John and his people were on Earth and about the Mogadorians would have helped the audience connect more to the story.
My favorite thing about the movie was Number 6. She had some serious skills and was a fierce, kick-butt warrior. I'm pretty sure if the Mogadorians showed up I'd want her protecting me instead of John Smith...well actually I'd want both. I want to live!
Overall I think is was a good movie and definitely worth seeing.