Wizards of the Coast no more exclusively defines Dungeons & Dragons than did TSR. If as you say it will live on in Pathfinder and the retro-clones, then it will live on, full stop, no difference from living on under WotC. Most of the retro-clones are especially slavish in their continuation of the classic rules. (I hope the same will happen for the Fourth Edition.)
I've watched D&D get worse and worse from the moment Hasbro bought WotC.
No confidence at all.
WOTC? I have a lot of confidence in WOTC and D&D.
Hasbro and D&D, pretty much zilch.
I think it is time for another company to handle the D&D brand.
Then again, a number of 3pp are already sort of doing that, such as Paizo and the companies out there producing retroclones.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.