1) Tolkien-esqe fantasy. My group (and me) can't stand steampunk, pulp magic, airships (though airships could work...somewhat), and especially anything anime or Japanese martial arts film related.
2) Some magic, enough that wizards aren't an unknown thing, but not as much as say, Forgotten Realms.
3) Either
A) At least some historical relevancy. Obviously, orcs and magic make that hard, but no plate armor, no armies of pike armed troops, in a setting that lacks early gunpowder.
OR
B) Don't even try to be accurate. People with puffy sleeves and rapiers face full plate armored orcs with halberds, in a nation where the feudal system isn't in place (but there is a monarchy), but there's no explanation why. And somehow, everyone can feed their gigantic professional armies.
I don't know why its one or the other, but I think I prefer the first, but sometimes need a break from gritty fantasy and need to play in a world where there is a profession in rescuing princess from witches and dragons, and gnomes have conversations with their +2 flaming toilets.
3) Have humans. And call them humans. Not "Earth-Children" or "Gythenians" or something like that. Elves, orcs, and other fantasy staples are not required, but if they exist, thet to must be called elves/dwarves/orcs. Or something similar. I have no problem with a campaign where orcs are called trolls or elves Sidhe. But when Elves are called trolls or "Qu'enlathine", then there's a problem.
4) I hate settings with "darkness and anarchy creep into the civilized lands. Now is the time for Heroes!" anywhere in their description. If I want enroaching evil, I'll take my non-evil land and stage a demonic or orc invasion. Faerun invaded by demons is fine. Midnight is not fine.
5) Maps! Maps and lots of fluff
6) Preferably something that I can use with GURPS, but really thats not a huge issue because converting is so easy.
7) Not a setting with an absurd amount of dungeons and ruined castles and "enemy lands". I want social interaction, traveling, and adventures that have action, high adventure, diplomacy, roleplaying, etc. I hate just killing things and taking their stuff.