There isn't much to see there yet, but 10 Downing Street has just opened an official Twitter account. Like a lot of corporate presences, it's based - in these initial stages at least - on their existing RSS output, and the free Twitterfeed web service. But I had a very interesting chat this afternoon with No10's new head of digital... and he's eagerly exploring what they might do next.
Just as interesting: I think I 'broke the story' when I mentioned it to my own (relatively) select band of Twitter contacts. I was subscriber no3. Two hours later, we're up to 23. Word travels fast.