^ If anything, it looks like PSP graphics to me, Look at the mountains in that image you posted. Ugh.
It might have better shaders, but I'm not convinced the 3DS is as powerful as the GC or Wii overall.
Again though, it's Monster Hunter, so it'll be the tough-as-nails addicting gameplay that will make or break it, not the visuals.
Resident Evil: Revelation should have taken care of your doubts (considering its a 1st-gen title too).
I'll say that the processor might not be as up-to-stuff, but it has more modern graphical effects that should allow the 3DS to look better graphcally than what was at least seen on the GCN. If we're talking about potential, then it can't match the Wii. However, if we're talking about real world results then I'm sure that the 3DS will have alot of games that will have graphical effects that make it seem to outperform the Wii, too.