The two tweets dealing with SBS reporter Karen Middleton's visit to Japan to cover the APEC meeting that appeared yesterday afternoon around 1.40pm show how social media has started to change the tone of debate in the public sphere.

In the first tweet - which has been retweeted in the image below - SBS rather unnecessarily tells us that Middleton is in Japan. It also tells us that US President Barack Obama was meeting Australian Prime Minister Julia Gillard. Nothing exceptional about that. News services are constantly spruiking their awareness of "important" events such as this "historic" meeting.

Then something strange happens when we get a new tweet a few minutes later from Middleton herself. Obama and Gillard are engaged in "mutual admiration"? Odd. No breathless recount of a handshake. No frenzied account of an air-kiss as the two leaders come together for the first time. Just an ironic reminder that reporters, too, have a sense of the ridiculous. Instead of puffing up the encounter, Middleton shrinks it down to a human, manageable size.

This kind of dealing with information would have been impossible without Twitter. It might have been caught on a microphone if the reporter had thought the mic had been turned off when in fact it wasn't. But it's not the very existence of the tweet, alone, that is significant. The tone of discussion in social media is qualitatively different from what we're used to on the (oh-so-polite) airwaves.

The meeting between the two leaders wasn't merely put into perspective, from the point of view of the average media consumer back in Australia. It wasn't just "mutual admiration" but, in fact, "the usual mutual admiration", so becoming completely un-newsworthy in an instant of critical reflection by the reporter. It's critical of the type of expression of solidarity we were habituated to watching take place between Obama's and Gillard's predecessors, Bush and Howard.

After all, Obama had the chance to visit Australia during this trip and had cancelled an earlier scheduled trip to Australia due to the Gulf of Mexico oil-spill crisis. This time, he went to Indonesia as well as Japan. But not Australia. So Middleton is seen here doing some of the critical thinking the average person does whenever they are subjected to the media's take on such an insignificant event as a brief meeting between two national leaders.