Or perhaps not. The Zelda demo, or "HD Experience" as Nintendo calls it, is almost certainly running at a native resolution of 720p, with no anti-aliasing and seems to be locked at 30 frames per second with v-sync engaged (subsequently verified with a good look at a 60Hz feed taken from G4's broadcast coverage of the event).
The lack of any kind of hardware AA, combined with the sheer amount of light sources might suggest that this is Nintendo's stab at producing a deferred lighting engine (particularly when factoring in the player-controlled time of day element), but on the other hand, the engineers may simply be showcasing the shading power of their new hardware.
As it is, much of the aliasing is obscured in a depth of field effect, with character shading being rather CG toon-like - similar to what Nintendo use on their Miis, but with better edge silhouette lighting to give it a kind of unearthly glow. The art style is certainly different to the run-of-the-mill Xbox 360 title, with a fast fall-off in lighting around an object: Link is bathed in shadow very quickly once he stops being directly lit.
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