The news that there will only be a single predator in AVP2 is really a mixed blessing. On one hand, we've already seen what that predator looks like, so there won't be any major surprises there. Although on the upside, that predator must be an elite hunter to be able to take on so many aliens throughout the movie. In a way, this news has just spoiled every fight scene in the movie, as we know that the solitary predator will have to survive until the end, meaning that any aliens he comes across during the course of the film are as good as dead.