I'd say it was pretty good. Which is to say not very good, but entertaining. The complexity the aliens needed was finally given to them, and the one liners that mar other action movies (cough, Van Damme, ahem) was not overdone, and actually worked with the movie. But it was obvious who was going to die. Isn't it always? Anyway, it was gruesome, the special effects were great, and Sigourney Weaver is always good. I didn't jump out of my seat once, but I was thoroughly entertained.