Unfortunately, neither White Wolf nor Blizzard could think of a good solution to this problem. We tried numerous strategies, including:
• Making the books more rules-heavy and less setting-heavy.
• Asking lots of questions of Blizzard before adding material to the books.
• Getting even more content from Blizzard that we could add to the books.
These measures weren't enough. Remember, each RPG book has the equivalent of two novels of information. We ended up with the following procedure:
1) We would write the books (using the above strategies), making stuff up when necessary. Then:
2) The good folks at Blizzard would check the manuscript to make sure that a) everything in it was consistent with both their vision of the Warcraft setting and the information that had already been presented in some other format (the video games, the novels, and the like); and b) that we didn't add anything that they didn't like.
3) The writers would then alter the manuscript as per Blizzard's requests, and we'd return to step 2.
This process -- while it eventually resulted in a great product that made everyone happy -- was long and arduous. The people at Blizzard spent a lot of time going through the manuscript and making requests, and the writers spent a lot of time making changes. In addition, the folks at Blizzard are busy people (for reasons that I assume are clear), so they needed to focus on other matters before turning to the RPG manuscripts.
Thus, the process required a lot of resources from both Blizzard and the writing team -- enough resources that we all started to wonder if the line made sense from a business standpoint.
In addition, we were not able to release the books as quickly as we would have liked, which irritated the fans. The problem continues to plague us: We started writing Dark Factions in December of 2005, and it still hasn't been released.
If someone else wants to create a tabletop RPG based on a licensed property, I have a few ideas that might help you avoid a similar problem.
• Allow the writers more freedom. Obviously Blizzard couldn't do this, because the Warcraft world is immense and spans many different media. If your IP isn't so gigantic, you might consider using the RPG writers as a good source of new ideas for your setting. You don't need to accept everything they write, of course, but you could go into the relationship assuming they'll come up with stuff you want to use.
• Declare that the books aren't canon -- that is, the information in them isn't "correct," it's just derived from an existing IP. Such a strategy has obvious pros and cons. I don't think it would be appropriate for the WoW RPG books, because people want to use them as reference for the setting.
However, one of the best things about tabletop RPGs is that you can take a world you love and do whatever you want with it -- but all those things don't "really happen" in the video game's setting. Expanding this freedom to encompass writers as well as players would solve this issue. However, both the writing and the companies' statements would need to make this distinction abundantly clear.
• Don't outsource the RPG stuff -- create an RPG division in your company. You might only need one or two employees in this division; the other help could come from freelancers. If the people responsible for creating content the game are within the company, they will have ready access to the information and people they need.
• Use a different release model. The standard system for an RPG line is to release one large core book and a number of sizeable supplementary books. Instead, you could produce smaller releases; perhaps each book could be one-half or even one-third the size of our books. Release perhaps six each year (instead of four). You'll have less content to fill and perhaps a bigger time cushion with which to fill it. (Note: I'm no marketing expert, and I have no idea if this plan would work well or not.)
• Use an online release system. This idea is similar to that presented above, but you wouldn't use printed books at all; you would release them all in electronic format. Doing so would allow you to update the books immediately in response to changing information (which was another challenge we encountered with the WoW RPG). It might also make the fans more forgiving of receiving content in bite-sized chunks, perhaps in some sort of subscription-based system. (Dungeons & Dragons looks to be experimenting with something similar -- we'll see how it goes.)
We experienced a number of other challenges while working on this game -- for example, after the books were complete but not yet published, new information appeared in the video game -- but the content issue was our biggest hurdle. We caught our collective foot on it. It may have even struck us in our collective groin. My hope is that it does not do the same for you. However, overall the books have been a very helpful learning experience that should hopefully be a lesson to all in what works and what doesn't when you want third-parties to extend your game world.