A little over an hour ago, Pat Phelan announced to the world that Twitterfone was live. Within 40 minutes or so, he had 1500 signups. Since the service is invite only at the moment, it might be a bit before you get your invite to the service!What is it? Twitterfone takes your voice, transcribes it to text, and tweets it on your Twitter feed, complete with a link to the original audio. This is bog simple and free.Local numbers are available in 10 countries, including the US, UK, and Ireland. Another 30 countries are coming in the next 6 weeks.