Currently, the only indication anyone is trying to get a Game through Auto pairing is a small piece of text saying "0 auto pairings", "1 auto pairing", or something like that. It's easy to miss.
I think when there is at least 1 Player trying to get a Game through Auto pairing, a message saying "Auto pairing available" should show up in the Lobby like a live seek. There would be a drop-down to allow the user to pick a particular variant and time control to accept.