So far they are solely working with Warners and have only licensed three teen-oriented properties; Pretty Little Liars, Gossip Girls and Vampire Diaries. However, if this works, I expect to see an explosion in this sort of thing. I can only assume they started kicking the can on this idea after noting the ASTOUNDING success of the 50 Shades of Gray sex books, which apparently started out as Twilight fan fic. Those things have made like a billion dollars (maybe literally), and I’m sure others would like a piece of that action.
The books would presumably be non-canon, and also I’d have to guess would be vetted by the owners of whatever franchise you’re talking about. Still, it in a way it would be like comic book work for hire; you wouldn’t own the rights to anything–I wouldn’t surprised if any characters you added to the books ended up being owned by Warners, etc., but you would earn a 35% commission on sales of your work. Legally.
The ramifications are too big to figure out immediately. But presumably you will eventually be able to do crossovers (Pretty Little Liars meets Vampire Diaries!). And if this spreads, comics could start coming out like this–do your own Spider-Man comics!!–or films or whatever.
Neat. I have to admit, I’m always interested in corporations who are smart enough to think outside the box like this. If this takes off, imagine what things might be like 20 years from now.