Kindle Worlds: Legal Fan Fiction?

I’m behind, but I’ve just come across the new “Kindle Worlds” – a paying platform for… Fan Fiction?

You can read the announcement here.

At the moment it seems they only have licenses for  Gossip Girl, by Cecily von Ziegesar; Pretty Little Liars, by Sara Shepard; and Vampire Diaries, by L.J. Smith. Meaning you could write stories with their characters, publish them on Kindle Worlds and sell them – for royalties – with this program.

I’m all for fan fiction, but I don’t know. This is getting a little… odd. Personally I don’t care if people write fan fiction for my books (I actually have some friends who borrow my characters for fun stuff)  but they’re not making money on it. Of course, I realize that under this program the eligible worlds would only be those Amazon has licensed, so even if they went berserk and got license grants from indie authors it would still be up to the individual author, so it isn’t as though they could “steal” the characters (at the moment – however whats to say a clause as such won’t show up in later kdp contracts) but even so it just sets a bad precedent.  Or maybe not. After all, Star Wars books may be licensed by George Lucas, but they’re really just fan fiction that the authors get paid for and that are “okayed” by the creator of the universe, so it’s the same principle. Or am I just over thinking it? What’s your opinion? (Please keep it nice, folks.)