The rumors I've heard was too many fan complaints about novels, and the authors were getting too hostile of a reception. The authors couldn't deal with trolls and flames, so instead of being professional and getting a thick skin, they just banned talking about their works.
Frankly, the WotC boards have lost a lot of usefullness with the increasing restrictions over the last few months. Can't discuss Forgotten Realms novels, on the message board of their publisher, when talking about a campaign setting that has much of it's metaplot unfolded in novels. *sigh*
Then there is the d20 Modern board. It's amusing, or sad, that in the official boards for their generic modern day/future RPG system you can't really discuss anything related to the modern day. Banning talk of anything related to real world religions and politics make sense when talking about a fictional game world on another plane of existence. In a thread about offhand references to throw into a futuristic game to remind players it's "The future", one poster put on a long list something like "an offhand reference to President Schwartzenegger". Funny as all heck when it was done in Demolition Man, but the WizO censored it. Or someone making a thread about pointing out how certain treaties about the use of space really restricted most space-based futuristic games unless treaties and/or world political bodies were significantly changed, that got closed down because mentioning the UN is a sure way to get a thread closed.
What's also sad is that WotC's own books break that rule in so many places. The d20 Modern Menace Manual talks about Scientology as an NPC organization (and a splinter/fringe group from them as a threat/nemesis organization), not to mention satanic cults (the Final Church from Dark*Matter) and the UN has secret black helicopter squads that operate above the law. Even suggesting one of those ideas would bring down moderator wrath. Interesting double standard, I can go into a bookstore and buy a copy of this book (or a little kid can stumble across a copy and browse), but I can't go online (where according to the COPPA you have to be 13 years old to post) and I can't talk about it.
Unearthed Arcana has sanity rules, with a good number of mental disorders you probably couldn't even mention, much less discuss without the thread being closed. The sanity rules also include rules for drug addiction (not even with a "mature" warning on it like the BoVD), and that's a lightning-quick way to get a thread closed, to even mention drugs. It's like the old-school Comics Code, it doesn't even exist. WotC will publish it as OGC to be freely republished throughout d20, and print it in multiple books, but don't even think to ask about it on their message boards.
I did notice that Dark*Matter went "down the memory hole" at WotC, and they removed any reference or archive of articles and pages about this old setting. I guess an organization which had the Catholic Church, Orthodox Church, FBI, FEMA, CIA, NASA, satanic cults, and Freemasons as major NPC organizations was too Politically Incorrect for modern WotC. Another reason we'll probably never see that great old setting revived officially.
Yeah, this is a rant too. Oh well, I guess I feel a little better having said it.