I've brought up Twitter before. Twitter is a micro-blogging service. You use it to "tweet" messages of no more than 140 characters. Your friends, colleagues and the general public can follow your Twitter stream and keep up with such urgent intelligence as, "Feeling bored," or "Currently surrounded by idiots." Or, perhaps, "Arrested."
"Arrested" was the tweet sent by US citizen James Karl Buck from an Egyptian police car (using his cell phone). He had been covering an anti-government protest. The message was received by the numerous followers of his Twitter stream both inside and outside Egypt. It triggered a sequence of events that ultimately persuaded the Egyptian security services to part company with him.
James Karl Buck's experience suggests that Twitter would be good for field workers and their support staff back home. One important facet of Twitter is that anyone can pick up your stream, and if it's interesting, you may get an awful lot of people listening in: People who can answer questions and provide timely aid. (Twitter is apparently also used by journalists to float ideas with their fans--free market research, in effect.)
I've wondered about Twitter's future. One intriguing thought is auto-posting. Can your cell phone use its knowledge of your context to create tweets automatically? Maybe. With GPS you could do, "Leaving work," and "Stuck in traffic on I-94," and "Hanging out at L'Abbatoir Impromptu" ("Shouting into the phone" would work, too.) Such "auto-tweets" would make it possible to produce reams of tedious information without the bother of actually keying it in. Or, from another perspective, it's exactly the sort of history that field personnel in potentially risky situations would want to make available.
I actually have a Twitter account (because I'm curious about others' streams) but I don't tweet. What would I say? The minutiae of my day are boring even to me. And my thoughts aren't organized enough to fit into140 characters, plus I prefer to express them (such as they are) here first. But I like the idea of Twitter...I just think it's for people who, like Mr. Buck, lead lives substantially more interesting than my own.