It's a Twitter thing. Let me explain.
If your tweet begins "@so-and-so," that means it will appears in the timelines of so-and-so plus whoever follows both you and so-and-so. Your followers won't see it, unless they also follow so-and-so (or go looking for it).
That makes sense -- you're so different when you're around so-and-so :(
It's a clever piece of design, which encourages you to have one-on-one conversations on Twitter without worrying about spamming all your followers.
There's a little hack to circumvent this -- just stick any character in front of the "@" and it will appear in all your followers' timelines. (For some reason, .@ is gaining currency against the more aesthetically pleasing ж@ and ‽@). The use of .@ suggests a kind of solicited eavesdropping, or spectacle chitchat. It suggests, "I'm talking to so-and-so, but I want everybody to hear this."
Understandably getting an .@ makes some people squeamish. It can be reminiscent of the IRL situation where you're chatting with somebody who keeps glancing past you to see if there's someone more important or interesting (or less abrasively fascinating) they can talk to instead. Is my attention not good enough for you?
My hunch, by the way, is that the squeamishness will diminish, and that .@ will lose that tarnish of mild pomposity and neediness, and get assimilated into the quotidian, perhaps non-pathological practices of putting yourself out there and getting all up in everyone's shit. Posting on somebody's Facebook wall once felt weird -- you've got the message function, why do you want "the whole world" to see that you guys should really meet up for gin fizzes, or are readying the launch sequence, or whatever?
But my question is: are we seeing this kind of not-quite-private, not-quite-public speech appear in science fiction yet? It's a very common trope of postcyberpunk in particular to have characters who are permanently online (perhaps via wearable devices, perhaps via surgically-implanted neural interfaces -- a lace, a jack, a plexcore, a jewel, a cranial crest, an inlay, an e-i, a Descartes fin, a think tank, a cornoggincopia) and therefore, as it were, permanently fucking around on social media.
I can think of some science fiction that comes close. A character in Iain M. Banks's Matter hilariously makes arch, melodramatic asides to a presumed swarm of surveillance lurkers. In Cory Doctorow's Down and Out in the Magic Kingdom characters sometimes hold one conversation out loud, and another subvocally ("Jesus, Lil, you are one rangy cowgirl"). There's Jennifer Egan's quasi-prescient Look at Me and innumerable tales of authenticity angst and self-fashioning under the social media gaze. People drop in on each other's consciousnesses pretty casually in an old Lorqi Blinks story of mine, "Fred." In Tim Maughan's "Limited Edition" Twitter is a ubiquitous and mandatory identity prosthesis -- for insight into a character, the ignorant gossip of online personae becomes just as important as an extended introspective soliloquy. The protagonist of Linda Nagata's The Red: First Light is a soldier who is networked not only with his squad, his spy drone, and his real time remote strategist, but is also the reluctant star of a reality TV show. The soldiers of Adam Roberts's New Model Army have naturalised their wiki-like comms medium and probably don't think of themselves as "using social media" any more than we think of ourselves as "using talking."
But I can't think of any true examples of "social living" (by analogy with social networking, social browsing, social learning, social tagging, etc.) in science fiction -- any works where the characters really seem to be surrounded by a penumbra of watchers, for whom they occasionally partly perform. Specifically, I can't think of any kind of ".@" moment.
Perhaps such moments are out there? Or perhaps they're coming?
Anyway, here's some Emma:
"Poor @MissTaylor!—I wish she were here again. What a pity it is that @MrWeston ever thought of her!"UPDATE: .@ruthlesscult suggests Rudy Rucker's Postsingularity (2007) is worth a look as regards living surveiled / monetising it; duly added to my TBR beard.
".@Papa, I cannot agree with you; you know I cannot. @MrWeston is such a good-humoured, pleasant, excellent man, that he thoroughly deserves a good wife;—and you would not have had Miss Taylor live with us for ever, and bear all my odd humours, when she might have a house of her own?"
"@MyDear, A house of her own!—But where is the advantage of a house of her own? This is three times as large.—And you have never any odd humours."
"How often we shall be going to see them, and they coming to see us!—We shall be always meeting! We must begin; we must go and pay wedding visit very soon. #parents"
"My dear, how am I to get so far? @Randalls is such a distance. I could not walk half so far."