That's because so much IS out of Halo 1 & 2 - the first person model, textures, sounds, animations - this is from a build a year old built primarily to be stable and to be subject to rigorous play testing. Even so, we can already see some impressive stuff. The Spartan models are fantastic, almost CG quality, which ironically makes them seem out of place in the very simplistic environments of the alpha. Also, the subtle animation tweaks are nice. Adaptive procedural animation makes postures on hills far more natural, and stepping AROUND objects to avoid clipping is pretty awesome. The Lighting and shadow model, especially on Snowbound, is excellent. And by far my favorite thing is the presence of what looks to be full AF.
The game, even in this year old build, can still look better than many next-gen games released today.
Here we can see a good application of real time reflection in the visor, as well as very nice ambient lighting conditions.
http://images.xboxyde.com/gallery/public/5195/798_0005.jpg
Another shot demonstrating how well things are lit - the subtle HDR is a nice touch.
http://images.xboxyde.com/gallery/public/5195/798_0053.jpg
Good examples of the adaptive animation.
http://images.xboxyde.com/gallery/public/5195/798_0058.jpg
That soft shader is just so amazing to me. Better than lost planet even because it persists.
http://images.xboxyde.com/gallery/public/5195/798_0060.jpg
More advanced particle system in action.
http://images.xboxyde.com/gallery/public/5195/798_0068.jpg
Another demonstration of how great the Spartan models are. I'm positive they're the same as the E3 trailer model. Also, the bubble shield refraction is really nice.
http://images.xboxyde.com/gallery/public/5195/798_0084.jpg
Again, the lighting and shadowing on the Spartans is so close to CG quality in my eye.
Anyway, I believe that the Vidoc showed plenty of promising elements.