Just thinking what are they going to call Hurt's doctor in the special? not his real name obviously and not Doctor (at least 10 and 11 wont call him that) ? Maybe call him 9, or even something generic like the 'outcast'.. or the 'Other' (The other..hmmm lol) ?
I think Hurt, assuming he is a Doctor his later selves believe is unworthy of the name, will still
call himself "the Doctor" because that's who he is and has, for centuries, thought of himself as.
As for what the Tennant and Smith Doctors call him, they may avoid the question altogether.