Recipes, fashion advice, super-colliders, and Greek history. All just a "tweet" away. Twitter has become far more than a novel platform for what you're doing right now. It's a finger on a cultural and informational pulse in real time.
This article, http://www.nytimes.com/2010/01/03/weekinreview/03carr.html?pagewanted=all sings the praises of Twitter in great detail. Twitter has quickly become the fastest, easiest, most succinct source of information on the web. Its usefulness, and to-the-point nature condense the fat out of information that might otherwise be out of reach for the time starved information consumer. It's very nature also squashes internet "trolls" whose only purpose is to reduce conversations to base and trivial flame-fights. It can become a forum for like minds, a platform for businesses, and even serve as a public service. I read once that if you wanted to be kept around, find ways to be useful. Twitter has done an excellent job of that, and it looks like it will be around for quite a while.