I'd be more concerned when they start forcing G+ on open platforms like the Web and Android. Maybe it's already started with Android KitKat shipping with Hangouts as the default messaging app.
The worst part is I can't even disable it if I am using my another SMS app, so now I have to clear two notifications for my text message and 50% of the time I usually end up in the Hangouts app where I don't want to be.
As mentioned in my other reply here, KitKat added an API which explicitly lets users change their default SMS app. The way apps did it in the past required using a hidden API and wasn't guaranteed to work.
