Just seen it and rather liked it. It 'feels' very different to the Alien films and more like a lot of British sci-fi literature. Probably due to the presence of a number of British/European actors and a British director, but it is more thoughtful and grandiose than the other films.
Problem is its plot is a bit muddled and vague in places, perhaps deliberately so if more is to be revealed in sequels and yes, a couple of characters do absolutely fuck all. Oh, and if you haven't seen Alien it won't really make much sense at all, I suspect. Fun stuff though and it looks fantastic.
One of the good things about it is that whilst it ostensibly answers some questions, the answers themselves leave you with even bigger questions than you had originally.
I'll give it 7 out of 10
indeed, saw it, i'm a big fan of the Alien series, saw all 4 countless times, obviously some are better than others, as for Prometheus the movies looks great, fantastic photography, cinematography, costumes, sets, technology, etc... as far as the scenario, it is quite muddy

