Notch has previously mentioned that he'd like to have "monster towns" in Minecraft, but today he described what he's expecting to put into the 1.8 update as "npc villages". I'd imagine these will be much the same thing, but perhaps the idea has moved on and we'll get more than just a monster hub? Interesting possibilities there. If survival mode is missing anything, it's someone to trade your crafted wares with. It'd be really something to be able to trade up a load of lesser resources for diamond or something. Notch's teaser post also mentioned that 1.8 will contain "at least one new mob, some interesting new combat mechanics, a new lighting engine... interesting farming, bigger incentives to explore."
It's looking like quite the update, but is clearly going to take some time to appear, too.