If you spent the time to read my post instead of impulsively lashing out at it (and actually trying to be funny, haha), you may have noticed that I said that textures and models are both a bit improved. I don't see more than that in the new screenshots you posted.
If you spent more time looking at the shots and watching the movies than lashing out trying to be actually funny (haha), you'd notice distortion effects, depth of field, and of course that nice glow the characters have on the surfaces hit by direct light. Notice, for example, on the edges girl's green hat. The Pokemon XD had very flat, dull lighting, and the only game I can think of that had a similar effect as the new game was Resident Evil 4, and that game ran in Cube's 6:6:6:6 color mode. Perhaps you're just not technically aware enough to realize that there's more to lighting than whether or not you have normal mapping.
For the 2 specific shots you posted, one also has clearly more dramatic lighting, but that is more of a setting / art direction difference than a technical one I'd say.
Nope, it's technical. Pokemon XD had one of the simplest lighting models I've seen on the Gamecube. It was nothing more than at most 2 or 3 infinite light sources, and Gouraud shading with absolute jack squat applied in the way of enhancements.
The new game clearly has a much more complex lighting model. I can't say how they're doing it, and I can't say if a 50% overclocked Flipper could do it (some people say Gouraud + environment mapping would work, both of which are in Flipper's feature set), but I can say with complete competence that the graphics engine for the new Pokemon game is significantly more advanced than the old one.
A lot of signs point to an enhanced TEV. It already was competent at distortion effects, but nothing it did was even close to the scale of what we saw in Red Steel (glass in the Dojo) and in Pokemon Battle Arena (green flame attack from that one little guy). The latter in particular I think would have obliterated the Gamecube's framerate, just judging by what the proton bombs in Rebel Strike did (and that effects is much more complex).
As for color depth issues, I don't think the dithering you're seeing is the result of 6:6:6:6 color mode. The Cube games that don't run in full 8-bit channel RGB have far more color issues than a little dithering on a flame, and there were games that ran in 8:8:8 that had zero dithering problems (Metroid Prime 2, for example). Throw in your copy of Sands of Time to see what I mean...6:6:6:6 color does
not look like what you see in Mario Strikers.