I can't stop thinking about this movie.
First off, I hate 3D. Actually, I hate post-production 3D. No matter what, your eyes can discern that something is wrong. Your mind has trouble figuring out what it is, but your eyes know. Prometheus was shot with 3D cameras, it is true 3D, and the difference shows. See it in 3D. See it in IMAX 3D actually. It's worth the extra ticket price. Many scenes are simply are simply astonishing in their realism and simplicity.
Next, this is a true science fiction work of art. It will leave you with questions. You will be coming up with theories as you leave the theater. It will keep you thinking. I've read many reviews where the critic counts this as a detractor. Those reviewers are simpletons.
And as an Alien fan, this movie is kid-in-a-candy-store.
Just see the movie.