Note: some spoilers within.
Prometheus is effectively two films, and neither one has the punch to succeed completely. In fact, one falters entirely.
The first two-thirds of the movie ask some big questions and tease us with themes of faith, creation and destruction and parenthood, but none of them are fleshed out fully enough. Much like our introduction to David, the first, and to a lesser extent, second act are deliberately paced and quite thoughtful. There are plenty of allusions and mythic-come-religious symbolism (the flashing cross in Shaw's dream-sequence, though, was an ugly, obvious step over the line), and the gentle pace serves to aid these ideas. The main cast are even given some time to develop during this period. The problem is what comes next.
By the time the third act comes around, everything they've spent the last hour and a half contemplating is totally discarded and we're left with something of a hollow monster-movie. Prometheus is too concerned with, and obviously self-conscious about, its ties with Alien that these ideas aren't given the room to breath that they require.
From the moment Shaw loses consciousness following Holloway's death, the film barely gives a single scene a moment to register. It bombards us with plot points and monstrous abominations. From this point on, the film is only concerned with getting Shaw into that 'other' ship and flying off into the great unknown. Whether this is a problem with the cut we won't know until the inevitable extended edition. What is for sure, though, is that the end falls flat. The much talked about caesarian scene is fantastic, and full of menace, but the blink-and-you'll-miss-it lead up, and the events that follow shortly after serve only to dampen the moment. Within the context of the movie, the single purpose this scene had was to provide a means of despatching the last Engineer, effectively providing a tentacled deus ex machina. The less said about the film's coda, the better: ticking of impregnation by extra-terrestrial is one thing, ending the film on a screaming infant xenomorph is another (not to mention the awful creature design exhibited).
The Lindelof argument is well-worn at this point, but had the script dealt with these elements more resolutely then the film would have been tighter overall.
This is my biggest gripe: the last act is far too muddled and rushed to really have much effect at all. It feels like a cut of a longer, better film, with particular scenes jarring painfully. It could be argued that the film mirrors Shaw's mental state having gone through what she just has, but it doesn't hold much water. Audiences will be left scratching their heads, no doubt. Should we see a 'director's cut', I'd wager that it would be a definite improvement over the theatrical version (obviously the problems at script-level can't be helped much regardless of length), but that is yet to be seen.
To further the scripts problems, much of the character motivation is purely in aid of plot contrivancies, which is a huge shame and tarnishes the great work that some of the other support put in. After venturing into an alien temple, two scientists (one of whom has been mapping the area) become lost, and unable to return to the ship. Not content with being cut off from their crew-mates, one indulges in a spot of reefer, while the other makes pillow-talk with a particularly aggressive looking snake. The parts are played with perfunctory stupidity. On the other side of the fence, though, are Fassbender, Elba, Theron and Green. Rapace is something of a mixed-bag, playing certain moments with an intense believability and poorly delivering others in a questionable accent.
Of course, Fassbender steals the show, but I actually thought Holloway's short arc was a triumph considering his relative lack of screen-time - Charlie's ultimate fate being the singular moment where a character's death meant much at all. Elba and Theron did well with the small parts they had to work with, the former elevating some truly awful material with as much professionalism as she could muster. Small looks here and there, and inflections in her speech sell what could easily have been cookie-cutter (if not worse) as portrayed by a lesser actor. Elba, as the ship's captain, displays the expected world-weariness, but with enough gravitas and wit that it works. If what we've heard with regard to scenes left in the editing room is true, their characters will be better served in the longer cut.
Scripting issues and thesps aside, Prometheus is basically state-of-the-art in marrying digital wizardry with gorgeous practical effects and sets. It is a complete knock-out in that regard, and I doubt a single person will come away without specific images burned into their memories. On approach to the moon LV-223, for example, the Prometheus is a spec against the enormous backdrop of a ringed-planet. On an IMAX screen, sights like this are genuinely breathtaking.
Further, the film absolutely oozes atmosphere. The brooding score, while ineffective at times, does its best to convey the marvels that the crew comes across. The first scene of the film, a wistful fly-over some incredible terrain before our first encounter with the alien race that apparently birthed us, is lifted with a beautiful musical flourish and genuinely had me in awe. The repeated journeys to the temple (granted, a little meandering on the script's part), gradually uncover more mysteries and wonders. There wasn't a moment where I didn't feel, at the very least, intrigued with what I was seeing. In its finest moments, Prometheus really does have you feeling like one of the crew.
There are issues, for sure - huge, fundamental issues - but the thing is, weighing all those things up, I can't help but love it. I've already seen it twice, and I plan on going once again before the end of its run. Whether that shows a lack of character on my part, for so easily being swept up in the grandeur, I don't particularly care: it's a fucking science-fiction movie by Ridley Scott and I'm a nerd.