We know that:
1) The cutscene character models will be present in realtime
2) The game will have improved lighting which I'm guessing is the cutscene lighting.
3) Improved shadows which again i'm guessing is straight from the cutscene to realtime
4) Improved AA but also notice how the cutscenes still have aliasing to them.
Here is the same segment before the gameplay changes into the pre-rendered scene.
PS3 realtime vs Pre-Rendered
Basically the same motto as Ryse "Play the cutscene."
Also the changes to the character models are subtle, but you can still see the difference.