Most people in the world do know milli (10-3) and micro (10-6). These are standard in SI units. http://en.wikipedia.org/wiki/SI Now if you talking about USA, maybe you have a point, but the USA is has less than 4% of the world's population.
4% of population? Indeed. But in this industry two things count: money and innovations. In both of them USA are among the world leaders.
My two cents: are "bits" a good name? Nope.
Are SI prefixes a better way? Not at all. Bear in mind, that most of the world currencies use two syllables at most. mBTC is already 4 syllables. Way too many to be used outside of the internet.
I am also not a fan of satoshis - this is also too long. And too unfamiliar for western speakers. Already mentioned "nakas" would be better, or something similliar.