Some new Metroid Prime 2 impressions have been posted at www.puissance-nintendo.com but unfortunately being French and all they are somewhat difficult to validate 
Here is a machine translation cleaned up by someone from the Ign Metroid forum:
Seems fairly credible, but even if its fake its about time we start getting excited for this game anyway
I'm sure you all still recall the first one, right? 8)
Edit: Oh and by "animation" I'm pretty sure they were referring to framerate, which will still be a smooth 60 by the sound of it.
Here is a machine translation cleaned up by someone from the Ign Metroid forum:
A playable demonstration of Metroid Prime 2 circulated two days ago within Nintendo. Is it the one we will see in E3? For the moment no one knows (fingers are crossed) but this demonstration caused much noise and was truly impressive. The technology will be the most advanced on the 128 bit Nintendo, pushing its limitations...
New special effects were developed by Retro Studios. These programming "visual effects" are drawn from the latest and freshest library source on the GameCube. The lead programmer explained in the last private meeting before E3: "the fact that Metroid Prime is an FPS allows a polygon gain because one does not model the hero, which allows a new management of the visuals. This enabled us to insert the latest special effects developed at Nintendo. There is almost no drop in animation which was our principal concern (...) The atmosphere will be more supernatural and the player will identify even more with Samus' conscience. What she will see will perhaps be only the fruit of her imagination... The programming takes much time and to promise a release for 2004 is a very difficult bet."
If Samus consciousness is really deteriorated by mirages or hallucinations, it will be a first on consoles to be confused by an FPS. But where Retro Studio will stop?! Waiting for the new demonstration will be very very difficult! What a year!
Seems fairly credible, but even if its fake its about time we start getting excited for this game anyway
I'm sure you all still recall the first one, right? 8)
Edit: Oh and by "animation" I'm pretty sure they were referring to framerate, which will still be a smooth 60 by the sound of it.