I saw Prometheus for the third time today and I've gotta say you notice more and more things the more you see it. However, I'm done until it comes out on BD.
Jon, I totally agree. Alien is amazing, but it is no different than Prometheus. Alien only has three memorable characters, one of which is only memorable because he gets the alien bursting through his chest. It leaves things ambiguous, just like Prometheus, as there is no clear origin to what happened on the alien spaceship.