It works better if you are in one of those cities to begin with. Then you still need a one-way to get home.
Works well for me because I leave from SLC, then bought a ticket from LAX-SLC to get home.
Just spoke on the phone to Delta, and was told that Delta employees could get priority passes to get get to SLC for some kind of big party to launch this flight. Don't know any more about it to date.
But was told there are still seats left for these flights.