Am I the only one who knows the source material on this? This game is based on Dreamwave's series "Transformers: War Within". It is considered canon, pre-G1, and is set during the civil war on Cybertron. (In the first issue Orion Pax is given the matrix of leadership, making him Optimus Prime, which is handy since Megatron just ripped the last Autobot leader, Sentinel Prime, to shreds.)
Anyone who has not read those comics, go get them or get some scans, and read them. This is the most awesome bit of Transformers fluff in existence. It's grim, dark, brutal and - wait for it - it has no humans at all! If this game turns out as good as its source material we're in for a real treat, guys and gals.