My prediction, regarding the post D&D IV world, is that all of that radically different stuff (you know, the things that made it "not D&D anymore") will be shed for 5e, resulting in a second wave of reactionary malcontents (like us), the 4e-gnards. Or whatever.
Anyway, now that it's Officially Too Late, I'll mention an idea I had about why 4e was so different from D&D. It's video games, obviously. Most of them take their character advancement rules from D&D--if everybody had spent millions of hours playing Dragon Warrior and Final Fantasy, like I did, then D&D itself is not interesting anymore, so if it's to be a brand in its own right it needs to be something besides that common DNA that makes up the bulk of video games.
Of course, D&D is much more than moving around the pieces of your character's abilities skill and powers, much more than inventory management, but the all-important exploration, discovery and improvisation aren't as visible looking at the rules. Ironically, I think 4e is lacking in those elements because of all the playing time taken up by the tactical miniatures game at its center.
Whatever your feelings about D&D V, every one of you Blognards should sign up for the mailing list for the open playtest and do what you can to make The New Game a retroclone too!