Re: Google Drops Who +1'd A Page In Google's Search Results - http://www.seroundtable.com/google-...
"Yes, the "your friend shared this on Google+" annotation was around for a long time after the +1 annotation disappeared. They are not quite the same thing, as the +1 annotation included things that friends had plussed out on the web, whereas the friend share notification is only for things shared on G+." - Mark Traphagen