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I honestly didn't know and don't know if this is new. I know Google has shown social profile links in the knowledge graph box since November of last year. But I didn't know if it was shown only while signed into Google versus not shown while not signed in.
In any event, former Googler, Pedro Dias, said on Google+ that he is now seeing his own social profile links (in his case just to LinkedIn) even when signed out. He shared a picture of it showing up for a search on his named.
I made a quick animated GIF showing these links and profiles when signed out for a few queries, including Pedro Dias, myself and Gary Illyes. Gary does not have social profiles either logged in or out.
Forum discussion at Google+.
