So where will reference material come from? Primarily
translations from
texts in spoken languages?
Yes.
Oh, and the next question is: What's the literacy
rate of any written
forms (as in, something you can put on paper) of signed languages
amongst the deaf population? Or are the orthographies symbolic in such a
way that reading it is similar to watching someone actually sign?
No idea, but it's definitely very low. Thus the need for sign synthesis.
Mark