Ann Handley of MarktingProfs asks (via Twitter, of course) a simple question: "Why do you use Twitter?"  Here's my not-as-simple answer:

I'm a software entrepreneur. I started using Twitter just because it was there and I wanted to understand what it was. But in doing so, I've come to realize that it is an important part of our rapidly changing information landscape. It is part of the ongoing communication technology evolution. Like technologies before it—mail, telegraph, radio, telehone, TV, overnight delivery, fax, e-mail, www, RSS, etc.—Twitter is creating countless new value propositions. There is no one reason why it is important, but it is very important.

Why do you use Twitter?