Since I've been living in KSA with my husband for the last two years my current residence is obviously in KSA...however, when they say you need a domicile in the USA what exactly does that mean? A place to live once you immigrate? If so, how do you prove domicile? Mail? My domicile in the USA is my mother's house...is that ok?

Here is what the Sydney consulate's website explains as domicile:
http://canberra.usembassy.gov/consular/vis...t.html#domicile

My husband has been living outside of the US for the last 4 years and will be proving his domicile with:
US bank accounts
US permanent mailing address (his parent's house)
Current washington state driver's license
Grad school acceptance letter
Lease on a new apartment
Arrangements to relinquish residence abroad (selling our car, one way plane ticket, etc)