That's what this post on Ragan.com asks, and from the comments, it sounds like the majority say it is. I can see it being rude if people are just checking e-mail or shopping on eBay or whatever, but really, live-tweeting about a session is perceived to be rude? I didn't know that. And, while I agree with those who say that just parroting the speaker's words isn't adding much, but that's pretty much all I have time to do if I want to keep up with what s/he is saying -- no time to add deep thoughts to the mix.
Hmm, maybe I should rethink my conference coverage strategies...
What do you think? Is it being rude to those in the room with you, or is it, as I always have thought, an acceptable if not perfect way to try to share what's happening in the room with those who can't be there?