Fanlistings are the invention of some Bavarian Janine who is now repudiating all responsibility for the monstrous institution they have become. Also known as TFL.org. It's that huge website that you have to register your fanlisting with and put their link on your listing's website and in return you can call it 'official' and 'approved'. Although, I think they have a rule now that you can't. Or shouldn't. Well, anyway, they're trying to make sure that there is only one listing for every topic. And if you didn't get the listing you wanted, well, that's bad luck. I am actually still fuming that I never got the colour yellow. Out of protest I didn't join the person's listing who got it, but made a clique for yellow instead. And it looks way better that the 'official' one! Ha!
Speaking of cliques, they have probably existed even before fanlistings became popular. They're basically the same, only that to join a clique you need a website. And they come for even weirder topics than fanlistings do.
Another big difference is that you don't have to check for other cliques for the same topic while for fanlistings there exist such terms as 'wishlist' and 'kill fors'. I have a wishlist, too, and yellow is definitely on it.