Everywhere you look these days, things are different. As time has gone by, we find that the deep jungle grows ever sparser. We can actually rely on our colleagues to help us, however amoral they might seem to be, or how obviously Chekov's some of their guns are. There's a new brand of Predator alien with an extra row of teeth, perhaps to make up for the overall sanitization of the mouth design. A man known for acting (Adrien Brody, The Pianist, The Jacket) can take the place of a man better known for bodybuilding. We may even find that, if we look in the right place, that it is disconcertingly obvious that we're on a different planet.
Indeed, Predators solves most of the problems of Predator. The supporting cast is no longer dead weight, and may no longer be accused of drowning the flow of the story in a silly series of B-plots. Substituting for an awkward friendship/betrayal/redemption arc is the show-stealing Nolan (Laurence Fishburne, The Matrix) in a small, yet critical role. The motif of predator and prey is played to much more strongly, and the final battle is no longer harnessed to an improbably elaborate trap.
Nevertheless, Predators also falls foul in failing, or refusing, to recreate the conceptual elegance of Predator's final act. It was the strongest of possible interpretations of the theme, and played marvelously to its actors' strengths. In its place, we have the inconceivable introduction of Predator politics, only to make possible a human/Predator alliance as a plot device, whose most favorable comparison must be to the similar, and similarly immersion-ruining alliance in Alien vs. Predator. It is not the mistakes that Predators made that make it so flawed, however--it is the risks it refused to take.