A colleague shared a story recently from Nature June 25, 2009 called "breaking the convention?". It discussed how blogs and twitter are opening up scientific meetings to those not actually there.
It's a great story. I've experienced this at several conferences already this year. I was able to follow based on the twitter stream in real time and then had a transcript of audience comments well afterward. You can do it too. Almost every technical conference today has a hash tag (e.g #e2conf) and every session has a hashtag with session number (#e2conf1). After the conference is over (or during the sessions) go to twitter, search on that hashtag and wallahh!, you have the insight. It's great to view the twitter log along with the slides to get the full picture.
Some go on to package up the tweets using a tool like printyourtweets.com and end up with a nice PDF suitable for archiving and sharing.
Glad to see this coming to the scientific community too.