Not sure how long it's been down, but it's been a while. Nothing on status.twitter.com. 

This reminds me what I'm going to talk about at the 140Conf on April 20. How we are fools to think that something like Twitter can run entirely on one company's servers.  

The Twitter guys should know that can't work, and should be planning on a resilient future, one where we can trust them because we don't have to trust them.