Nouredine Abboud: The PC version is a more tactical game, which means that you can give direct, specific orders to your team-mates, which you can't do on the Xbox version. You also have the tactical map, where you can create way points and plan your whole strategy, which you can't do on the 360. The levels are designed specifically so you can benefit from the new gameplay elements.
I cannot stress enough how happy I am to hear they are taking this approach. I wish they gave Vegas the same treatment.