Staying connected at conferences

I was a bit surprised to see a tweet today from Gartner analyst Merv Adrian where he mentioned that he is at the Gartner BI conference in London and a delegate in the audience had asked him to stop typing.
He was using a “noisy” Lenovo before switching to the quieter iPhone.
What surprised me is that whenever I attend conferences, there are people all over the place using laptops, phones, iPads, and other devices to capture information as the speakers do their thing. It might be that they are taking notes, tweeting important soundbites, or sending comments on the talk to colleagues – whatever they are doing it is interacting with the speaker.
I can understand why Merv switched devices, he represents Gartner after all so he is a host at the event. But what should the rest of us do when taking notes at a big conference and asked by a fellow delegate to ‘stop typing’ because they find it a bit of a distraction? Agree with them that conferences should be all about an expert talking on stage for half an hour, or suggest to the person that we have moved on and are living in a more interactive age?
Perhaps you can type your responses on a postcard?

Conference crowd