Rather unfairly, on Friday lunchtime at last week’s NHS Confederation annual conference in a rainy Manchester, I tweeted David Williams of Health Service Journal to suggest that the only place #Confed2012 was trending on the personalised panels of people at Confed2012. [See footnote 1] Half the people in the press office had already seen the conference’s hashtag in the list and voiced the same assumption, before realising that Twitter shows a personalised trending list by default – the difference was that David had tweeted the first before getting to the second.
There was a lot of social media wackiness going on in the press office, such as seeing a tweet by someone sitting a few yards away and thanking her out loud for the historical contextualisation. But certainly NHS Confederation made some clever use of Twitter. Its suggested #Confed2012 hashtag was heavily used during the event, and was a good choice – everyone calls the event ‘confed’ and it’s shorter than the full word (although a few people used #NHSConfed2012 as an alternative). It also set up an account just for the event. The number of people tweeting on the conference and using the hashtag led my friends on Guardian Healthcare Network to set up a list of people tweeting at the event (including myself).
NHS Confederation press officers watched tweets with #Confed2012 closely and were quick to join the conversation – the NHS Confed account apparently responded to David and I’s Twantering  although it seems to have deleted this since, and media manager Francesca Reville certainly hit back quickly when I started moaning about Manchester’s signature weather.
To what end? Confed always gets a lot of coverage from healthcare publications – HSJ is always there in force and there were at least five of us writing for various sections of the Guardian. But it’s impossible to cover comprehensively, because at some points there are as many as nine sessions running simultaneously, often of high quality (such as this lightly-attended but fascinating session on how Wales reckons it can do things faster because its NHS is not marketised and split between commissioners and providers). Some tweets from delegates, who are all NHS experts, mean these events get attention beyond those in the room. And during the keynotes, it lets audience members discuss what they are hearing. (It would have been fun to have had a Twitterfall  of messages behind Lansley when he was speaking. Although his press officers may not have appreciated it.)
It’s also a great opportunity for writers to promote their coverage of an event. Although organic search  is a bigger source of traffic, a hashtag is a great way to link articles unambiguously to an event, particularly when there is likely to be numerous pieces over several days. To do so through search engine optimisation could lead to a lot of articles with similar, rather dull, headlines, but a hashtag at the end of a tweet works fine.
I suspect writers aren’t yet using hashtags to their full potential (with a few talented exceptions such as former colleagues Ben Whitelaw and Nick Petrie at the Times, who have just won a commendation at the Digital Media Awards for the #cyclesafe hashtag supporting that paper’s campaign of the same name). Hashtags certainly make sense for an event (and it probably makes sense for the organiser to choose and promote the tag as NHS Confed did); for a campaign like #cyclesafe; and for anything where interaction is vital rather than problematic, given you can’t control what anyone does with the tag.
I’m not sure whether writers make enough use of use ‘unofficial’ hashtags, the kind not invented by a publisher or an event organiser but that just take off… that could become a trending type of Twixploitation. 
 Trending: something is trending on Twitter if it is ranked as one of the top words of collections of words, often starting with a # and therefore generally known as hashtags, recently used on Twitter in a certain country or city. Twitter now shows a personalised list of trending hashtags by default, although you can switch to a general list.
 Twantering: Twitter bantering. Just made this word up, but there’s a lot of it about.
* Correction – someone else got there first in 2010. Obviously I’m using the top definition here.
 Twitterfall: live ‘waterfall’ list of tweets using a certain hashtag, displayed at an event. Somewhat high-risk, unless you restrict it to tweets from people you trust.
 Organic search: searches made through search engine, the source of a big chunk of most site’s traffic.
 Twixploitation: exploitation of Twitter, rather than a twin-pack of chocolate-covered finger biscuits. I made this up as well, but it feels like a word we need.