Interesting conversation(s - there are a few going on simultaneously, as usual).
I think an important distinction should be made between
creative input and
influencing creative process. A parent company (Hasbro) can influence creative process without having any direct creative input. If Hasbro says "You need to make X amount of profit per year or we'll pull the plug," that influences creative process in that WotC needs to make sure they meet those financial goals. But it isn't the same thing as creative input, which would be Hasbro saying "We want rainbow fairy gnomes in the Player's Handbook!" Or "Cleavage on every hardcover book because boobs sell, especially Drow boobs!"
Here's an example of how creative input and influencing creative process are quite different. I'm currently revising the draft of my first novel. My wife has no creative input whatsoever. Now our marriage and life together may indirectly
influence my story; and truly, whether or not she's willing to tolerate me going off to the coffee shop for hours on end while she toils away with the rugrats will certainly influence my creative process. But in no way is she directly offering creative input, unless I ask her, which I generally don't.
Now it seems that Mearls & Minions have concocted an ingenious strategy to keep D&D viable without negatively impacting creativity by creating an excess of low-quality splat books. They've created a kind of "buffer zone" between the tabletop RPG and Hasbro by embedding the RPG within the larger D&D brand name, which will have numerous avenues of revenue. So while Hasbro will be looking at the bottom line for D&D, they won't necessarily be looking at the different components within D&D. So all that matters is that "D&D" is profitable; if the brand is successful as a whole, Mearls & Minions have even more creative freedom to do what they want with the tabletop RPG.
On a completely different subject...
I don't think WotC is hoping to steal Pathfinder diehards. But I think you may underestimate how many people player Pathfinder, and other games in the extended D&D family, that are loose in their loyalties and, all things being equal, would like to play the official D&D game,
if it is good/like old times/can accommodate a wide variety of styles, etc.
I actually agree with @
TerraDave that 5E is going to be very successful, perhaps very
very successful - as in, regaining the throne and then some. The problem Pathfinder faces is that they've painted themselves into a crunchy, rules heavy corner. I thought that they were going to do a "basic" version of the game a couple years ago, but it only manifested in the Beginner's Box which wasn't the beginning of a simpler variant but the "easier entry ramp" (to use Essentials lingo) to the more complex Pathfinder game.
But the thing is, not everyone want an uber-complicated game. Most people want a simpler core, but with the
option to get complex. This is what 5E offers and Pathfinder doesn't, 4E didn't, 3.5 didn't.
The other difference in 5E that I think will equal long-term success is that was designed, and is being developed, for long-term success - not simply the quick-fix, quick buck. It is like Mearls & Co have learned the fine art of delayed gratification and are willing to actually prioritize quality over quantity - and I think they've learned this through watching Paizo thrive.
Hmmm...this isn't exactly how I remember it. There was a sitshtorm from the beginning, and not just the "Its not my D&D" or Slaviscekian PR debacles. Discerning gamers were having issues with the rules from the beginning, particularly the Grind and having to mess with damage and attacks and all that. The problems were evident right away. I think what became clear later on is that WotC wasn't able to fix it, despite giving it a kind of half-hearted shot (Essentials). Remember, Essentials was planned like a year after launch, so WotC knew there was a problem.
Don't forget that many people had the rules before they were published by first of PDF Gate (remember the core rulebook PDFs with the little rainbow code bar? Not that
I owned such a despicable, illegal download but "I just heard about it"

).