How do conferences use social media?

One of my pet hates is when conference organisers set up social media sites - specifically Facebook and Twitter - for a conference and then don't follow through on the commitment during the conference. A library conference a few years ago did this, had 'Follow us on Facebook' and 'Follow us on Twitter' plastered all over the conference home page but when it came to the conference itself, absolute silence. As someone who couldn't attend that conference I was more than just a tad annoyed as I expected the conference organisers to take that commitment seriously and maintain the ongoing flow of communication. Not so.
Back in February this year I attended VALA in Melbourne and was struck by how well the social media, specifically the tweeting, was managed by conference organisers. Not only were organisers observed to be actively tweeting during sessions (from the conference identity) but responses to questions were prompt and agenda updates provided regularly. They showed how it could be done.
Just the other week I followed the ALIA Biennial 2012 conference from afar and was again impressed by the way conference organisers ensured that the conversations flourished on Twitter and Facebook throughout the conference. Not only was there direct engagement but they also made obvious use of scheduling tools like Hootsuite to manage programming details, share session papers, and so on.
This week I'm following another library conference and so far I've been quite disappointed by the lack of engagement from conference organisers on Twitter and Facebook. There appear to be a few photos going up on Facebook today (one lopsided) but next to no action on Twitter itself since yesterday and then only a handful of comments came through (indeed most of the tweeting seems to have occurred primarily pre-conference). The bulk of the tweeting is coming from participants at the conference and even that is reasonably sporadic, obviously the proportion of tweeters is significantly lower at this conference than at either VALA or ALIA2012. Which is a shame as I'd really like to know what's going on and if I can't discover that from the tweet stream than the whole thing becomes of little use to me and all I come away with is a sense of dissatisfaction and feeling that it could all be done so much better.
The moral of the story?  If you are going to promote social media streams at a conference then you must also accept the responsibility for ensuring that you maintain an ongoing outgoing and engaging dialogue with others via those streams.  If that means utilising a roster so that various staff can share the load, then do that.  If that means using other tools like Hootsuite to schedule tweets and/or posts than do that. Don't expect the social media stream to maintain itself, that's your job.

sigh, rant over...