So people have been arguing over what the exact nature of David's role in the movie. Here is the answer:

 

LMAO!! excatly

 

Could have been a fantastic movie given the premise of our creation. In the end just another dumb alien movie

 

 

I thought it was pretty cool. A few scenes definitely arent for the squeamish.

That spoiler picture from vadster is pretty funny because its true, kind of confusing with what was going on.
Disregarding the fact it created more questions than it answered, it was a pretty good movie. I don't like to think too hard when watching movies, so maybe ignoring that fact made it more enjoyable.

 

Saw it on Friday, and most of what's been posted in here is dead on. It was good entertainment, but it wasn't quite the taut sci-fi/horror movie that Alien was.

 

Finally saw this. I can't let go of the glaring discrepancy in size of the Space Jockey from Alien vs. Prometheus... They're not even close.

 

http://m.youtube.com/watch?v=-x1YuvUQFJ0

So much wrong with this movie. I was completely irked by nearly everything the crew did.