Thanks for that link, John. I've saved the pdf for future reference.
The online knowledge base for FTM offers this definition for the address fact under "Commonly Used Facts" in their tutorial on how to add and edit facts:
"Address – Addresses can be useful for recording the contact information of living relatives or for recording the area where an ancestor was known to have lived."
It doesn't get to my question, though -- the difference between an address and a residence fact. One thought I had is that "residence" is fairly general (i.e. Bob Smith lived in Smithville) where address might be specific (i.e. Bob Smith lived at 123 East Street, Smithville).