I'm tempted to close this thread because it is likely a flamewar waiting to happen, but I'll leave it for now. It's on thin ice, as is anyone who wants to intentionally sink it.
EDIT: ...And Umbran followed my same thoughts.
There are two problems with the supposition in the first post:
1) Saying is not doing. I really don't see an impetus to make WotC want to devote time and resources to the very thing mentioned here; their efforts are on the future, not the past, and releasing something with no intention to support it wouldn't be very viable, I would think.
2) The original post doesn't take into account the "buy-in" that Paizo is planning. Anyone remember those "long tail" and "1,000 true fan" discussions a while back? (The two concepts are found in wikipedia now, too.) Paizo is offering a "buy-in" with their Open playtest of their product, which is to me a pretty smart plan.If they can get even a small core of their fanbase to feel a part of this product, they'll have no interest in any "compendium" WotC would target at them, and the rest of WotC's fanbase likely wouldn't even know what it's really for, and wouldn't care. With a strong but small fan base, Paizo could live pretty well doing what they love.
I'll also say it now: No one at Paizo has ever said they intend to "challenge WotC", and I would imagine most of them would think it daft if someone DID think they would be taking the lion's share of D&D gamers with them. But they know how big their fan base is now, and if they can make a move that gets most of them to keep following them, then they'll be quite happy, I would imagine.
So in the end, "My Dad can beat up your Dad" discussions aren't really productive. If BOTH products are available in the marketplace, the gaming community is BETTER off, not worse.