Another "Battle: Los Angeles" Trailer
This one is longer than the one I posted before. It gives us more clues about how the alien invasion actually works--it seems like the rain of meteors are infantry drop-pods a la Starship Troopers rather than orbital bombardment weapons, although the trailer does depict ships and helicopters being destroyed by them.
Perhaps the "meteor shower" consists of rocks or projectiles of some kind as well as infantry drop-pods. After all, using your infantry as bullets or artillery shells strikes me as a really bad strategy.
On my alternate-history forum, in which I found the trailer, someone theorized the aliens were semi-aquatic. This could explain an invasion of Earth--which has an ocean--rather than worlds where there are resources but no population to fight (think Mars). It's also more creative than a lot of invading aliens, which seem to be land animals if not humans-in-suits.
(However, the end of the trailer features something coming out of the ground, which seems to indicate the aliens had something on Earth before they invaded, something fairly big.)
I do like the helicopter with some of the Marines and the refugees getting smashed as soon as it takes off--in real life, death often comes suddenly and brutally rather than in a predictable fashion.