The basics
The main tag on Twitter for the event is #ECF2011 – if in doubt use this tag.
For administrative announcements about the event follow @ecf2011.
The sessions
Each individual session has its own tag, a two-figure number. The session convener should announce this number at the start of the session, and if in doubt check the post about the session here on the ECF Live site. Tags for a session should hence be #ECF2011 and – for example – #07. Both tags need to be used.
In addition the public debate on Monday 21st at 1700 has its own Twitter tag – #ECFdebate
Twitter list
A list of all attendees at the event who have submitted a Twitter name has been created – you can find that list here (still under construction).
Flickr
If you take pictures during the event please tag them ‘ECF2011′. We would appreciate it if they were Creative Commons / Sharealike licensed so we can use them here on the ECF Live site.
Jon is one of the facilitators of #ECF2011, having also helped out in 2010. He's a website designer and trainer, and is best known for his role in the Atheist Bus Campaign. 
I’ve set up WTHashtag to archive all the tweets on the ECF tag which can be found here: http://wthashtag.com/Ecf2011.