I think maybe some of you aren't seeing the bigger picture here. There is lots of talk about what is powering the demo, but for me the fact that this engine (designed for video games) is pulling this off at all is astonishing. If you ever really wanted a glimpse into the future of video games, here it is. Just how far into the future, is an interesting thought.
On the hardware debate, I think people are forgetting just how good Crysis looks. I see no real reason why this couldn't be handled at a respectable framerate. It's the first time we have seen this engine in such a setting. It has Fantastic art direction coupled with the most advanced engine on the planet.
I would be quite disappointed in Crytek, after finishing off with "Realtime, like no other" if they used any tricks or cheats at all.