A few details for Alien vs. Predator were revealed in a PSW chat with Rebellion's Jason Kingsley.
According to the interview, the game features three player classes - Aliens, Marines, and Predators -each harboring its own special abilities and powers.
A "rock-paper-scissors" balance system has been implemented in multiplayer and there is also a single-player campaign for each class.
Story wise, the game is set 30 years after the original Aliens and involves a new planet that has been colonized. While digging for minerals, ancient ruins are discovered and, as you can guess, all hell breaks loose.
Kingsley said during the interview that the game will "dovetail directly into the 20th Century Fox movies, too", and Rebellion included loads of ideas into the game that were previously cut because of hardware constraints.
The game is expected sometime in 2010, and while platforms have not been announced, it's easy to assume it will land on PS3 and Xbox 360 at the very least.
More through CVG.