That is almost a counter example though, he has 32000 people in circles while g+ is still quiet limited. If g+ was to go away he could easily redirect the domai

That is almost a counter example though, he has 32000 people in circles while g+ is still quiet limited. If g+ was to go away he could easily redirect the domain and build his core following back up fairly quickly. This of course is a lot different for say a company that has worked very hard building up something like a Facebook following that while susceptible to marketing messages aren't likely to go out of their way to follow the company to whatever online presences they create.