its cool everyone can't know everything, i wouldn't know most of that if i didn't have a degree in computer science....
anyway, speculation aside nintendo has kept the exact specs from being known so until then there is no way to really tell how powerful the system will be exactly
but back to the speculation, i'd say it will actually be close to the 360 in terms of graphics. heres my reason: the price difference is about that between the high end and almost high end graphics cards from any given company currently available, ati for example has the x1800 and 1900 (high end) available for $450-600, the next step down x1600 retails for about $300
the differences are minimal are mostly speed related, the graphics look almost the same between the two cards except for certain bells and whistles (this is where the 360 and esp. the ps3 will outstrip the wii) supported by the more costly cards