Ugh, the first movie was awful and this one just seems so... I can't put my finger on it but a lot of films nowadays share the same general 'feeling' especially American sci-fi/horror, Resident Evil, Doom etc. It could be the filming style, I'm not sure.
In that trailer we're shown pretty much everything, which leaves... what to see in the movie?
In both the original Alien and Predator movies, in my opinion, they were based around the 'Oh carp, what the hell is it!' factor, using the atmosphere perfectly, especially in Alien.
Where as in these movies it's basically, 5 minutes into movie, see the alien/monster in full, removing any chance of the 'What the hell is it?' factor > introduce generic characters > que predictable "Oh noez we have 10 hours until the govnernment activates nukes" plot > finish with big CGI based alien/monster fight.
Another factor which I think makes the AvP film/s bad is the fact both Aliens and Predators are in it, sounds stupid, but in their original films they were pitted against humans which made them seem far superior, where as in the first AvP film, the fights between the Aliens and Predators made them appear to be nothing special.
But yes, rant over.