Dan this update really downgrades my experience of chat on google. I want to see a list of online/busy/offline people, I want to know the people I'm talking too are available. I know this can't be said about SMS, but thats why I choose to use an IM client as it's more advanced that SMS.
Please include this and allow visibility settings, aside from SMS integration, this is definitely something that people want. Even if this is an option within the app to display.
I appreciate you trying to hide technology from the user, but seeing if a person is available to chat immediately isn't exactly the most difficult technology to understand.
I don't want to message my gf / friend / parent asking if they're around or waiting for a response, I want to know that she's available to chat. Surely this is an obvious thing to include