Aloïsius said:
I think this thing stay "top secret" usualy.
Hmm, too bad...then I'll simply claim the designers did it because they like the concept better and found it more "cool", and think they can sell it well enough to the new target audience because it doesn't have 30 years of "baggage" attached to it.
This is not about taste.
Imagine they sell "a new edition". 4e. Implying that this is somewhat an improvement over the past. And then, you buy the book, and discover that those are the same. I would feel cheated, because I already have those old books.
Sure is, from where I stand. If I like something in D&D, and D&D switches to a new ruleset different enough to make conversion difficult (and I follow that trend), and the stuff I like is published with the new rules (and I got the cash for it

), I'll buy it. I have the BECMI ruleset, including cosmology, I have the MotP 1E, I have the 3E version, and if I had the cash, I'd go for the Planescape versions of the Inner Planes and Etheral Plane at least (as I mentioned elsewhere already, the Outer Planes always looked more like in BECMI D&D with me anyway

). And apart from making conversion easier, it's always a lot of fun to read what a new author comes up with for the stuff you like.

At least I never felt cheated with that. Same goes for updates campaign settings, by the way.