That's the general difference in the verb form, yes. It fits fine with
"I stay in a hotel whenever I can/I am staying in a hotel." But I was
considering strictly the two sentences:
"An old man and woman live across the street from us."
"An old man and woman are living across the street from us."
Do you think a speaker of today is seriously trying to convey by the
second one that he doesn't know how long the elderly couple have been
there and they might not be there much longer?
Or does he really just mean that their home is across the street? That's
what I see happening, more and more.
It's a tricky point to explain. All that significance about impermanence
only works if there is another form, the timeless one. If people use
"-ing" all the time, the distinction is lost.
I think the use of "-ing" where it didn't used to be some sort of modern
habit (like "to my husband and I" is a modern habit) and is said because
it sounds right. People echo each other, and that's how language
changes.
I'm not trying to stop the tide, nor am I very upset that the tide is
changing, but I want people to *notice*.
Anyway, in this case, the original question was about "There is an old
man and woman living across the street from us." The word "living"
probably just persisted from that.