I've always enjoyed the concise, the pithy, even the terse. Like many others, over the last year I've found myself tweeting and being involved in that conversation far more than blogging. Is this a bad thing? I don't think so. Much of Twitter is trivial but so is much of everything, and at least it has the virtue of being briefly trivial.
However, some of it isn't trivial. Today I've seen a campaign launched to speak up for my profession which is, like many others, under threat of possible cuts. The call is for professionals to tweet what they do and why it matters, to sum it up in 140 characters or less. It's a campaign that makes us focus on the essentials, it doesn't allow for rambling arguments or going off the point. It shares the discipline of short forms of writing generally.