Ok, I’ll play:

WTF is Twitter?

What is it? 

Twitter is a community of friends and strangers from around the world sending updates about moments in their lives.  Friends near or far can use Twitter to remain somewhat close while far away.  Curious people can make friends.  Bloggers can use it as a mini-blogging tool. Developers can use the API to make Twitter tools of their own. Possibilities are endless!
Ok… so how does it work?

You can send updates in three ways: send a text message from your mobile phone, type a message from the Twitter site, or instant message from Jabber or Gmail chat. (support for AIM and other chat services coming soon!)   Start by texting the word help to 40404 if you’re in the United States.  For international folks, we have different numbers.  Write us and we’ll give you yours.