I think this is it. They knew their best way of beating Facebook was going to be incorporating Plus as tightly into Google as possible. If you remember, it even

I think this is it. They knew their best way of beating Facebook was going to be incorporating Plus as tightly into Google as possible. If you remember, it even integrated into Google searches for a while in a very obvious way (though they rolled back how visible that is). I'm not a developer, but I'd imagine it's not a single thing they can remove, that it's mixed into of every team's code, all over the place.