My experiences very much match Anne... I don't really even like Twitter (the impossibility of real conversations is maddening), but it has been incredibly useful to me over the past year, and I am glad I have got a sort-of network there now.
On attending a conference by Twitter

I am attending the New York Times Conference Food For Tomorrow which is addressing two ambitious questions: how to feed the growing world population, especially the world's poor and how to reverse poor eating habits in the developed world. All the big and not so big names are here: Mark Bittman, Michael Pollan, Marion Nestle, Sam Kass, Mario Batali, etc.

I am not actually present at this conference because it is far and expensive. It's the kind of conference where--I'm not making this up--you get a portable phone charger in the goodie bag. (What? No mug?) Rather I'm "attending" by Twitter hashtag  which means I'm reading the stream of tweets tagged  #nytfft .

I am retweeting a lot of the tweets to the #geoeducation  community which has to be annoying all 7 of my followers on Twitter and perhaps others reading the Food for Tomorrow stream. If I remember, I try to remove the #nytfft  before retweeting so I'm not duplicating tweets. I'm successful about 25% of the time. Need to work on that.

I am fortunate in that this is the sort of conference where there are a number of people tweeting and they are doing a rather good job of it. When tweeting, it's important to record the speaker's main points in as many of the speaker's actual words as possible. I imagine this is difficult to do, especially in a panel discussion where you have to identify who said what, keeping part of your brain attentive to the conversation and part of your brain attentive to the tweet you are sending out.

"Tweet-tending" a conference does leave gaps. I know I am missing points from the speaker that I would have found interesting or meaningful. However, what I am getting--and would not have gotten had I attended in person--is the community or collective view; those points that others, particularly lots of others, have found interesting or meaningful.

When the speaker makes a meaningful point, it shows up quickly and repeatedly in the Twitter feed. The wording sometimes varies but the main idea is there. Take, for example, Mark Bittman's contention that the way to feed 9 billion people is to eliminate poverty. 

That one popped up right away in the Twitter stream. Lots of people tweeted it. And it kept popping up through the rest of the afternoon. Sometimes, it was attached to the idea that wealthy people (I'm paraphrasing) don't go hungry, and sometimes not.

But obviously, this was an idea that resonated with people. If I had been sitting on the hard little folding chair in the room and heard that, I would have gotten excited because I think this an idea that needs to be talked about and mulled over. But I wouldn't have known, for sure, if anyone else felt it as interesting or meaningful as I.  Even assuming I was able to connect with people at dinner or the social hour,  it probably would have been a while until we got around to the Big Ideas of the conference.

On Twitter, there isn't much chitchat. You have so few characters that it's down to business.

I am not saying that Twitter is in any way a replacement for face to face conferences or networking. Absolutely not. Rather, I find it to be a supplement; a way for me to participate in opportunities that are not afforded to or affordable for me.

As an aside, you get to see on Twitter some of the conflict that you might otherwise miss. There are a couple of tweeters who are upset that there are so few farmers speaking, not to mention how this conference is completely out of reach for the poor. So you get tweets like this: "The tweet stream coming out of @nytimes#NYTFFT is incredibly lame. People posing with Porsches, pics of turkeys, pontification. Sayonara."  (Porsche was a sponsor and attendees were encouraged to post and tag their picture next to the Porsche) I don't know that would have been on my radar had I actually been there.

I'm still learning how to attend a conference via Twitter and share it appropriately. Of particular concern for me is how to archive it so I can return to it later and have it make sense. (Hat tip to +Laura Gibbs, Chief Drum Banger for Curation and Archiving of Your Content)

There are a few good practices to archiving via Tweet. Make sure, for example, that you clearly note when a new session or speaker begins and who is speaking. So far, there have been enough people posting photos of the speaker(s) taking the stage that this is always a good opening tweet.

 Also, as I noted above, remove the original hashtag. Otherwise, it's like getting feedback that makes a microphone screech in the original stream.

Maybe I'm just old fashioned but I think you should acknowledge the people you find especially effective. At the very least you should follow them since Twitter is all about the follows.

And finally, if you are going to try and participate, give it the time it deserves. Interestingly enough, tweet-tending was not something I could do as part of multi-tasking at my desk. I could look at a few emails but that was about it. I had to pay attention to the stream so I could make sense of it.

I will confess Twitter is not my favorite social media platform but for this, it works. I would even go as far as saying it's worth learning how to use Twitter just to take advantage of opportunities like this.

Yeah, I know. I can't believe I said that either.
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