Well, I really have to admit, that I'm shocked, how the critics raise their voice regarding this third movie of a simply iconic franchise.
Certainly Fincher does not have the right script and ideas to make his version stand in line with the original movie. But his film has its moments - and lots of it.
First of all, he terminates this fucking shit about the marines being dumb buggers, which was being brought to us by Cameron.
Second of all, he combines both main elements of the first movies: Horror and action. The alien is revived in a new kind of looking (and some pretty bad CGI-effects regarding our time), but with its original purpose. It's a smart hunter and terrible killer.
Nevertheless Fincher's version relies on some british-accent-talking Neo-Christians and transform Ripley in a messiah kind of way. I never particularly like that in movies or elsewhere. So the general depths of the former parts isn't reached, but damn I care about the story and some of the characters - fair enough, I had a good time.