For me, this relates to my remark upthread, that [MENTION=2067]Kamikaze Midget[/MENTION] objected to, about some D&Ders apparently caring more for minor details than thematic resonance.
The organisational structure of the planes seems to me, in and of itself, one of the lesser elements of a cosmology. Changing it around is like drawing a new map for some other campaign element. (And the 4e MoP had a one-page sidebar explaining how to redraw the map to get the Great Wheel back.)
What I think is more important, in the question of fidelity or revision to what has gone before, is whether a designer is starting from scratch, or trying to work with what came before. To my mind there is no doubt that the 4e designers saw themselves as falling into the second camp, and were correct to do so. Worlds & Monsters even sets out their methodology (and it is the openness about methodology that makes me regard W&M as one of the best GM guides put out for D&D, because it is the only one that addresses the use of story elements for story purposes from a metagame rather than an ingame framework).