The "true next gen" is X360 and ps3, because it is a continuation of a sales pitch tried and proved, horsepower sells games, Nintendo is going the other way so it will be the "other gen" of sorts, trying another selling strategy, memorabilia, easy controls and affordable price (Sony said that PS3 will be aimed at enthusiasts), of course it will run multiplatform games, however, at lower resolutions.
If it is the right step to be taken will remain to be seen, a revolution indeed it is, not for tech specs per se but for the selling strategy it implies, i believe it will give nintendo an edge and will help to increase the gaming community in numbers, but it is just an old man´s belief...