Would it not be possible though to have the entire node be editable? Could you have just a link that says edit node and have the node form in the popup?

Also there doesn't seem to be a way to make the body or title editable inline. I think there might be a use case for individually editing fieldgroups, but I think most people would like the whole node form in a popup or maybe have a feature where each field could have a hover edit link that would launch that field in a popup or something.