I talked and played with a couple people who were trying to do a Thursday night CoC night but it seemed like they mostly placked on lackey...which I did not understand because I thought the guy who was doing lackey stopped updating it (I could be wrong).
At its best, Cthulhu Night Online is client-agnostic. It's about people making time to be online to play at the same time as others on any card game client.
Personally, as a Mac user, the only client available to me is Lackey, so that's what I use. Reports from OCTGN users after a Thursday night is there are more Cthulhu players there than what I see pass through Lackey's lobby.