@juga0 points out in #14 that we don't actualy know whether an ellipsis really language-agnostic. What about non-western languages? what about non-alphabetic languages?
My suspicion is that if users of those languages are using e-mail they are at least exposed to US ASCII at some level, but i have no data to back that up. and i also don't know anything about the cultural implications of the ellipsis (outside of western writing), broadly speaking.