Here you can talk about what you think the new NPC villagers will look like!
Personally, i think they are going to look like the passive animals, but standing up as a human/steve!
There is already a skin of a pigman, (not pigmen the nether pig) That is shown in your textures in the minecraft.jar!
I'd hope for humans. I mean... block-thieving stickmen and explosively-antisocial four-legged aliens are cool, but bipedal pigs... er... ^^; Meh. I'll take humans any day, especially if there's ever gonna be an adventure mode with a plot, text, all that...
How so? People are already done in SMP, pigmen don't have any reason to converse with you normally (unless they do the trade-y thing), and it would probably give the game a bit of an Animal Crossing-y feel, which is generally upbeat and cheery, which in my opinion, is needed in contrast to the hells and horrors of the night.