What we don't know is what in the world will they use next? They took out white ppl, black ppl, and azn ppl... what other types of "ppl" are there!? Of course there is brown ppl, but i kindof feel that brown ppl (people from arabic descent) were addressed in Nightfall (vabbi). Indian people could have been clumped into "brown" / arabic people, but their culture and mythology (and armor and weapons) are vastly different from arabic people, making them an option for the next chapter.
Another race they could dig up could be hispanic people, though i would be annoyed if they did because i think they (physically) are a lot like brown people if you just paled their skin a bit. Brown people have wavy hair and so do hispanic people, and also it wouldn't be as big of a "culture shock" if you went from brown to hispanic, as azn to black. However the mythology and locations of hispanic locations are completely different from anything addressed in the previous chapters. Though there would be some overlap in the rainforests (even though i don't think rainforests and jungles are the same thing...) the landscape of latin america and culture was not touched in Nightfall.
Also, they could clump "hispanic" people into native american people, as they could explore the culture of the aztecs and such. THAT would be a more exciting addition to Guild Wars. Like Elona, where the "south" of Elona is actually similar to the "south" of a real world place (Africa south of the mediteranian -istan- is vastly different from northern africa -vabbi-), they could make the south of the new map the rainforests of some people like the aztecs, and the north echo the Great Plains' native americans.
Europe was probably addressed completely in C1, and so were modern "americans" i guess. So the next "hosts" of guildwars are probably either Indian, hispanic, southern native american, or northern native american (or a mix of several of these cultures). I'm guessing it will most likely take place in the hispanic/native american culture, but you never know- What do you guys think... did i forget about a major culture that Anet will find?
EDIT: ugh this post is getting ugly, yes race was a VERY bad word choice. The purpose of this post was to narrow down on what C4 was going to be based in, as there isnt really much choice, unless Anet decides to make their own culture, they will probably loosely base it off of a real world area or culture not remotely close 2 the past 3 chapters(i hear ppl arguing about how its not based on real world races... im pretty sure Nightfall is hinted with africa as there are barely any caucasian cpus, and same with C1 and C2, but you know what i mean by races, not the context which Survivor jumbled them in, as all the contestants were really "american" in culture

And someone posted "theres more races than that" and started naming dozens of races, that well, exist, but guildwars seems to use cultures and people more generally, for example nightfall's location was a blend between fiction and several places and people that were "brown" not just african, middleastern, indian, and what not (demonic