Ok, i'll take an extremely easy question for starters. Take this trailer http://www.youtube.com/watch?v=1Kvl31g77Z8&hd=1 and move to 0:32.
Question: NOT the character animation, but the interaction with vegetation. Will Crysis 2 on the PC have that level of interaction? I know the leak isn't a good example as it's not the final game, but the interaction there with vegetation was something like 10 times WORSER then in crysis 1.
Don't use the leak as a basis for anything, it's nowhere near representation of the final product. As for your question, yes, vegetation (but naturally, not
all vegetation) is interactive. The video you linked is a feature-set of CryENGINE3 and there's going to be little/nothing that CryENGINE3 can do that won't make it into Crysis 2.
"Next gen" is something that strictly belongs to the console world, as the pc is an ever evolving technology. So, the question rephrased:
Will Crysis at LAUNCH on the PC have the features intended for PS4(?) and XBox720(?) implemented?
CryENGINE is a platform that is upgradeable. Without knowing exactly what the 8th Generation consoles are capable of, it's jumping the gun at the moment to start speccing for it. See 9:45 in the following video: