Alerinne starts an interesting conversation over on the forums about bringing WoW back into "Medieval Fantasy" -- swords and sorcery instead of alien Draenei and spaceships. Normally, the conversation about MMO genre runs along the lines of too much fantasy, but many players, it seems, would rather be running around with axes and fireballs rather than lasers and robots, especially in a world that is so akin to traditional fantasy (Orcs, Elves, and so on).
To be fair, World of Warcraft has always had its own charms -- Dwarves have always been able to fire guns, something that's not usually in traditional fantasy, and even Goblins with their zeppelins (and Gnomes with their engineering) have always added a little extra flavor to the game that goes beyond purist fantasy. But it's true -- zones like Netherstorm and even Auchindoun go a little overboard for real fantasy fans.
So hopefully, as we hear in the thread, we'll see a little more traditional fantasy setting in Wrath of the Lich King. So far, lots of things we've seen there have had a bit of a Norse trend to them, from the Frozen Tundra to the Vykrul race found in the early zones. But there's more to this expansion that we haven't seen -- Icecrown Citadel is an old-fashioned ice fortress, according to the lore, and with the movement of Dalaran and the rumors of dragons up there, we definitely have a possibility of a return to the magic and steel that made this series so popular in the first place.