I like the previous Aliens movies, and really like the fact that the director, Ridley Scott, always has uber-strong female characters. In this movie, I was mistaken as to which female was going to be the last one standing! And the action, once they got to the new planet, was almost non-stop! There were plot twists I didn't expect, and yes, lots of explosions. And aliens of a few different kinds. The IMAX 3D experience made it so that you felt like you were in outer space, and walking yourself on an alien world. The next best thing to being there, without having to be one of the characters who dies in a creatively gruesome manner.
So my recommendation for a great summer flick is Prometheus!