As far as I can tell, Turin is the only one still pursuing this theory, and he hasn't made a lot of headway. About five years ago he was trying to prove his theory by producing molecules with heavy hydrogen, which would smell different by his theory and the same under conventional theory, and the results were inconclusive. He seems to have moved on to other areas.

His theory has a fascinating way of explaining what it means for novel smells to be judged similar, but nobody can find a mechanism that would allow it to work. That's not proof that it doesn't work that way, but the conventional theory is proving very productive in research, and his hasn't.