First, there are those cuisines that have, at least in part, penetrated into pretty much all sectors of America-- maybe, Italian, Mexican, and Chinese?
Then there are those that are fairly well-known to more urban people and those who eat out often-- Japanese, Thai, Vietnamese, Indian, Greek, “Middle Eastern”, French, Spanish, etc.
Finally there are those that are still somewhat obscure to many but seem to be gaining in popularity and prevalence-- Ethiopian, Afghani, Russian, Cambodian, etc.
Obviously, these characterizations should be taken with an intense grain of salt; they’re colored by my own experiences and will differ a lot depending on the location and the cultural background of the person. Also, it assumes a certain Angloness, I think, which I’m uncomfortable with (and, personally, am not), but I think it’s safe to say that the average, say, Vietnamese-American is also probably more familiar with Mexican food than with Ethiopian food*. So anyway, the above is just a rough guideline-- if you feel that Chinese food is extremely exotic while Afghani food is a staple for most Americans, feel free to proceed according to your own feelings.
What I want is to hear about the other cuisines! Those that most of us may not be familiar with. So tell us about that killer Ainu appetizer or the amazing things Angolan people do with their vegetables.
*Also, this is obviously America-centric-- unfortunately, to be more inclusive would make the topic basically meaningless.