Well in pure physics I'd say it's theoretically possible, but there are a lot of other processes in Crysis handled by the GPU and CPU that the consoles can't handle. Also, I say theoretically, because we haven't seen anything close. LBP has great physics, but they are only in a VERY small area, whereas in Crysis there is actual WIND. Yes, wind that effects the entire island, spreads fire, determines the direction trees fall, moves the grass etc.
One thing that they can't handle is the AI. The AI on the entire island is constantly interacting. Console games tend to have an AI "bubble" where the AI begins interacting when you get within a certain range of them, but in Crysis the AI doesn't stop. If you attack a camp you can be 2 miles away and that camp will still be hunting you and rebuilding.
Also as you said as well the GPU's are clearly far more limited than current PC GPUs. Btw, I'd just like to point out that Crysis itself isn't that good a game. In fact, it's pretty average for an FPS. It's just made some amazing technology breakthroughs.
